SEOUL — North Korean leader Kim Jong Un appeared on Thursday to claim the country had developed a hydrogen bomb, a step up from the less powerful atomic bomb, but outside experts were skeptical.

Kim made the comments as he toured the Phyongchon Revolutionary Site, which marks the feats of his father, who died in 2011, and his grandfather, state founder and eternal president Kim Il Sung, the official KCNA news agency said.

The work of Kim Il Sung "turned the DPRK into a powerful nuclear weapons state ready to detonate a self-reliant A-bomb and H-bomb to reliably defend its sovereignty and the dignity of the nation," KCNA quoted Kim Jong Un as saying.

DPRK is the acronym for the isolated North's official name, the Democratic People's Republic of Korea. A hydrogen bomb, also known as a thermonuclear bomb, uses more advanced technology to produce a significantly more powerful blast than an atomic bomb.

North Korea conducted underground tests to set off nuclear devices in 2006, 2009, and 2013, for which it has been subject to UN Security Council sanctions banning trade and financing activities that aid its weapons program.

An official at South Korea's intelligence agency told the Yonhap news agency that there was no evidence that the North had the capacity for a hydrogen bomb and believed Kim was speaking rhetorically.

The impoverished North Korea and the rich, democratic South Korea remain technically at war after their 1950-1953 conflict ended in a truce, not a treaty. The North has threatened to destroy the South and its major ally, the United States, in a sea of flames.

Despite the underground tests, the North has been seen as short of achieving the capability to put a nuclear warhead on a missile. If the claim is true, it would indicate advances in the North's pursuit of nuclear weapons.

"I think it's unlikely that they have an H-bomb at the moment, but I don't expect them to keep testing basic devices indefinitely, either," said Jeffrey Lewis of the California-based Middlebury Institute of International Studies at Monterey.

It was possible the North was referring to the technology of boosting the yield of a nuclear device, possibly using fusion fuel, Lewis said.

North Korea claimed in 2010 that it had successfully developed fusion technology.

Assessing progress in the North's nuclear program is difficult because no one outside a close circle of leaders and experts in Pyongyang knows what advances have been made.

The North has also boasted to have succeeded in miniaturization of a nuclear warhead to mount on a ballistic missile, a claim disputed by US and South Korean experts.

(Reporting by Jack Kim and James Pearson; Editing by Tony Munroe and Nick Macfie)

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NOW WATCH: NUKE EXPERT: North Korea's recent activity at a nuclear test site is 'just a bluff'

The Korea Central News Agency reported that while visiting a historic military site Kim Jong Un announced that North Korea is ready to detonate an H-bomb.

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A senior North Korean ruling party official and a top aide to leader Kim Jong Un has died in a car accident, the state news agency reported on Wednesday, the latest dramatic demise in the close circle of deputies to the country's leader.

Kim Yang Gon, who was a secretary of the Workers' Party and the head of its United Front Department, the unit that handles the North's ties with South Korea, was Kim Jong Un's "closest comrade, a solid revolutionary partner", KCNA said.

Kim was part of a high-level delegation that held talks in August after the rival states exchanged artillery fire, raising tensions to one of its highest points in recent years.

Those talks produced an agreement that ended the standoff and for the two sides to reopen dialogue to improve ties.

Kim had grown visibly closer to Kim Jong Un recently, appearing alongside the young leader at various farm and factory inspections and diplomatic meetings.

He was an experienced adviser with a broad understanding of foreign affairs, according to Michael Madden, an expert on North Korea's leadership.

"With regard to South Korean policy, Kim Yang Gon had a very good social network and was a good interlocutor for the North with the South."

South Korea expressed condolences in a message from its Unification Minister sent through the Panmunjom truce village on the militarized border, an official said.

Skeptical reports

Kim Jong Un has dismissed a string of top aides since he took over when his father died suddenly in 2011.

In 2013, he purged and executed his uncle Jang Song Thaek, who was once considered the second most powerful man in the country, for "anti-revolutionary crimes."

KCNA said Kim died on Tuesday in an automobile accident at the age of 73. It gave no details of the accident.

Impoverished North Korea's road network is badly maintained and car ownership is rare, yet several high-level officials have died in traffic accidents over the years.

In 1976, an official said to rival to then-president Kim Il Sung died in a car crash. In 2003, a predecessor to Kim Yang Gon died in a traffic accident and in 2010 top official Ri Je Gang also died in a car crash.

"North Korea has a long track record of suspicious deaths around high-level officials," said North Korea expert Andrei Lankov. "Most die either because they are machine-gunned, or they die in car crashes".

"There are almost no cars and security for high-officials traveling in cars is extremely tight. Given that, one is bound to be skeptical about any such report coming from North Korea."

(Editing by Richard Pullin and Michael Perry)

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A team of IT analyst recently looked at North Korea's Red 3 operating system. And YouTuber MJD Productions was able to get his hands on their OS.

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North Korea announced on state television Wednesday that it had successfully detonated a "miniaturized" hydrogen bomb.

The announcement came hours after South Korean officials reported an artificial earthquake 30 miles north of Kilju, where North Korea's primary nuclear test site is located.

The US Geological Survey measured the magnitude of the quake at 5.1, the same magnitude reported after North Korea's most recent confirmed nuclear test, in February 2013.

Despite North Korea's announcement, many geopolitical experts remained skeptical of the country's claims of a successful hydrogen-bomb test, undoubtedly because of North Korean state media's tendency to exaggerate or outright lie about happenings in the isolated nation.

RAND senior defense analyst Bruce Bennett wrote in an opinion piece for CNN that it was unlikely that North Korea had achieved a successful hydrogen fusion bomb considering that the country's three previous nuclear tests appeared to show a difficulty in mastering a fission weapon.

Bennett did note that there was another possibility:

That possibility was echoed by Joe Cirincione, the president of Ploughshares Fund, a global security foundation:

Other experts on Twitter expressed skepticism as well:

Others are noting the similarities in some measures between a 2013 nuclear test and Tuesday's:

Here's North Korea's full statement, translated to English by NPR:

Chosun's first hydrogen bomb testing was completely successful.

The tens of millions of fighters in our nation embraced the battle cry of the Party with hearts full of boiling blood... 

The strategic determination of the Chosun Workers Party has led to the success of our first hydrogen bomb testing on January 6, 10 a.m., Juche 105 (year 2016).

This test, which relied 100% on our wisdom, our technology and our power, we have proved the accuracy of the technological resources behind our newly developed test hydrogen bomb. We have also proves scientifically the power of miniaturized hydrogen bombs.

The experimentation of our test-hydrogen bomb was carried out safety and perfectly, proving absolutely no negative effects on the surrounding natural environment.

This hydrogen bomb testing elevates the level of our nuclear weapons development. The complete success of our historic hydrogen bomb testing has proudly elevated the DPRK to the ranks of nations possessing nuclear weapons. Our people have boasted the dignified spirit of the nation, with the best nuclear restraint.

The hydrogen bomb testing, carried out by our nation, is a defense mechanism to protect the autonomy and survival of the nation from the increasing nuclear threats of the enemy powers, centered around the US, and reliably guarantee the peace and safety of the region.

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BEIJING (AP) — North Korea's main ally China said it "firmly opposes" Pyongyang's purported hydrogen bomb test and is monitoring the environment along its border with the North near the test site.

China plans to summon North Korea's ambassador in Beijing to the Foreign Ministry to lodge a strong protest, spokeswoman Hua Chunying told reporters at a daily briefing Wednesday. China made a similar protest after the North's last nuclear test in 2013.

Wednesday's reported test was performed in defiance of the international community and in contravention of its earlier denuclearization promises, Hua said.

"North Korea should stop taking any actions which would worsen the situation on the Korean peninsula," Hua said.

Environment bureau technicians were monitoring conditions near the border but air quality near the bomb site was within the normal range, Hua said.

In the longer term, North Korea should return to long-stalled six-nation denuclearization talks hosted by China, Hua said. North Korea abandoned that process in 2009, saying it would continue its nuclear program to produce a deterrent against alleged threats from the U.S. and other enemies.

While she made no mention of measures to respond to a test, analysts say Pyongyang's proceeding against Beijing's objections would seriously harm a relationship already under considerable strain.

That will likely include agreeing to tougher U.N. sanctions against Kim Jong Un's hard-line communist regime and possibly unilateral trade restrictions that could hurt the North's moribund economy.

Despite that, China remains the North's most important ally and trade partner.

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North Korean defector and author of "The Girl With Seven Names" Hyeonseo Lee explains what life was really like living in the country until she fled at the age of 17. 

Produced by Jenner Deal. Camera by Will Wei.

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16 fascinating facts about North Korea.

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Beijing (AFP) - China is unlikely to take strong action in response to North Korea's claimed test of a hydrogen bomb, according to experts who say Beijing prefers the devil it knows to the uncertainty that could follow a confrontation.

And whether Pyongyang would even listen is highly questionable, they say.

Governments around the world have long pushed the Asian giant to moderate its wayward neighbour's bad behaviour, arguing that Beijing's support for Pyongyang gives it particular influence over the hermit kingdom.

But that is ever less true, experts say. Relations forged in the blood of the Korean War -- with the countries once called "as close as teeth and lips" -- have taken a licking since Kim Jong-Un took control of North Korea following the 2011 death of his father.

"China's influence on North Korea is becoming weaker and weaker, the main issue is that the North's leadership do not listen, they are very stubborn", said Zhu Feng, an expert on international relations.

Pyongyang, he added, may believe it can "exploit" its relationship with its main diplomatic protector while Beijing is distracted by tensions with other neighbours and the US in the South China Sea.

Beijing -- which regularly calls for calm on the Korean peninsula -- has become increasingly frustrated with its neighbour's antics, a feeling undoubtedly exacerbated by its fourth nuclear test.

Unlike his father Kim Jong-Il, Pyongyang's current leader has not visited Beijing since coming to power.

Last month, he dispatched his all-girl pop group, the Moranbong band, to serenade China's top leaders in what was widely seen as a sign of warming ties, potentially heralding a trip.

But while they were in Beijing, Pyongyang announced it had developed an H-bomb and the band suddenly headed home on the eve of their performance, leaving relations in the deep freeze.

Only four days later Kim signed the order to begin 2016 with the "thrilling sound of the first hydrogen bomb explosion." 

- 'Risky, irresponsible, reckless' -

Despite the shock developments, Zhu said, China's foreign ministry stuck to familiar language, firmly opposing the nuclear test and -- yet again -- calling for the resumption of the moribund six-party talks.

Commentaries in state-run media Thursday were also true to form, scolding the country but falling short of a call for direct action from Beijing.

An editorial in the government-published China Daily described the test as "risky, irresponsible and reckless", but said the problem was best addressed through the "collective wisdom and determination" of the international community. 

There was no mention of what, if any, steps Beijing could or should pursue on its own.  

In any case, Pyongyang is unlikely to prove receptive to Chinese measures.

"Kim Jong-Un might feel that he has, you know, sort of a nothing to lose kind of mentality", said Wang Dong, an associate professor at Peking University's School of International Studies.

If so, that leaves the international community in a "very difficult situation", he said. "How are you going to deal with a guy who feels, who believes, that he has nothing to lose?"

- Keeping the regime afloat -

The test, two days before Kim's birthday, was a striking act of defiance in the face of warnings that Pyongyang would pay a steep price if it continued pursuing its atomic weapons programme.

The three previous tests in 2006, 2009 and 2013 triggered waves of UN sanctions, largely focused on individuals and companies linked to the weapons programme.

But China, a permanent member of the Security Council, argues that dialogue is the only way to moderate its behaviour and remains a major exporter to North Korea.

According to figures from China Customs, the country exported more than 176,000 tonnes of refined oil to North Korea in the first 11 months of 2015 -- more than the total for 2014 -- and over 23 million tonnes of grain. 

But underlying everything is Beijing's desire to keep North Korea as a buffer between it and the prospect of US troops stationed on its border in a unified Korea.

"China keeps the Kim regime afloat with fuel supply, food assistance and an opening out of diplomatic and economic isolation," said Yanmei Xie, a senior analyst at the International Crisis Group. 

"For Beijing, a nuclear armed North Korea is uncomfortable and disturbing", she said. 

"But a regime collapse in Pyongyang leading to mass chaos next door and potentially a united Korean peninsula with Washington extending its influence northward to China's doorstep is downright frightening."

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On Thursday, South Korea told North Korea's leader, Kim Jong Un, that it would troll him on his birthday in response to his latest nuclear test. On Friday, Kim Jong Un's 33rd birthday, South Korea followed through.

Steve Herman, the Southeast Asia bureau chief for the Voice of America news site, tweeted:

Back in 2012, the South Korean newspaper Joongang Daily observed that Kim's wife owned a $1,600 Dior handbag.

Also:

The announcements were made perhaps to appeal to a population that is facing a historic drought and famine.

SEE ALSO: 16 fascinating facts about North Korea

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NOW WATCH: A North Korean defector tells us what life was like under a dictatorship

Next week's issue of The New Yorker is set to feature North Korea's supreme leader, Kim Jong-un, as a baby playing with toy missiles.

Kim's regime drew worldwide attention earlier this week when it announced that it had successfully detonated a hydrogen bomb, which would have represented a significant advancement in its nuclear arsenal.

However, South Korea, the US, and outside experts all cast skepticism on that assertion and suggested that North Korea actually detonated a more conventional atomic bomb.

According to The New York Times, the eccentric Kim is believed to be in his early 30s.

Here's The New Yorker's new cover:

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Last September, Aram Pan was one of 150 people to join the largest helicopter tour of North Korea.

Organized by Juche Travel Services, the tour included sweeping views of the North Korean countryside as well as the capital city of Pyongyang, which has incredibly imposing concrete-dominated architecture. Pan has visited the locked-down country nine times over the last two years, and each time he uses a 360-degree camera to capture the full North Korean experience.

Here's the video he shot of his helicopter ride.

Pan has also visited restaurants, banks, shipyards, and he's even taken a ride on the North Korean metro. 

Here's what the helicopter looked like on the inside, which Pan captured with his 360-degree camera. 

The interior looks like it's straight from an American home in the 1960s.

You can check out the full 360-degree experience of the helicopter here, along with Pan's entire portfolio on his website DPRK 360, or his Facebook page. 

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Real-estate mogul Donald Trump said on Saturday that North Korea's supreme leader, Kim Jong Un, deserves "credit" for taking over his country at such a young age.

"If you look at North Korea, this guy, I mean, he's like a maniac, OK? And you've got to give him credit. How many young guys — he was like 26 or 25 when his father died — take over these tough generals," Trump said in Ottumwa, Iowa.

The Republican presidential front-runner said Kim's willingness to push aside generals and "wipe out" his uncle demonstrated why the US needs to treat North Korea's nuclear arsenal as a serious threat.

"And all of a sudden — and you know it's pretty amazing when you think of it — how does he do that? Even though it is a culture and it's a cultural thing, he goes in, he takes over, and he's the boss," Trump recalled. "It's incredible. He wiped out the uncle. He wiped out this one, that one. I mean, this guy doesn't play games. And we can't play games with him. Because he really does have missiles. And he really does have nukes."

North Korea drew worldwide condemnation earlier this week when it detonated what it claimed was a hydrogen bomb. If true, North Korea's nuclear weapons would have to the potential to be far more devastating. However, experts widely believe that the erratic North Korean regime had actually tested a more conventional nuclear weapon.

During his Iowa speech on Saturday, Trump also said his plan to de-escalate the region is for the US to put pressure on China, which has been North Korea's longtime benefactor. The billionaire businessman accused the Chinese government of ripping the US off for years.

"Here's what we do. We tell China," Trump said. "We rebuilt China. They have taken so much of our money with trade. They have taken everything. They have taken our jobs, our money. ... They've taken so much. And literally, it's one of the great thefts in the history of the world, what they've done to our country."

SEE ALSO: DONALD TRUMP: Here's how I'd handle that 'madman' in North Korea

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NOW WATCH: A North Korean defector tells us what life was like under a dictatorship

SEOUL (Reuters) - North Korean leader Kim Jong Un said the country conducted a hydrogen bomb test as a self-defensive step against a U.S. threat of nuclear war and had a sovereign right to do so without being criticized, state news agency KCNA reported on Sunday.

North Korea's fourth nuclear test on Wednesday angered both the United States and China, which was not given prior notice, although the U.S. government and weapons experts doubt the North's claim that the device it set off was a hydrogen bomb. 

"The DPRK's H-bomb test ... is a self-defensive step for reliably defending the peace on the Korean Peninsula and the regional security from the danger of nuclear war caused by the U.S.-led imperialists," KCNA quoted Kim as saying.

"It is the legitimate right of a sovereign state and a fair action that nobody can criticize," he said.

Kim's comments were in line with the North's official rhetoric blaming the United States for deploying nuclear weapons on the Korean peninsula to justify its nuclear program but were the first by its leader since Wednesday's blast.

The United States has said it has no nuclear weapons stationed in South Korea. But it has been in discussion with the South about deploying strategic weapons on the Korean peninsula after the test. Media said these could include nuclear-capable B-2 and B-52 bombers, and a nuclear-powered submarine.

Experts believe the test, which produced a seismic tremor of 5.1, too small to be a proper hydrogen bomb test, was designed to set the stage for a rare general meeting of its ruling Workers' Party, the first since 1980.

Kim noted the significance of the timing of the test as being held in the year of the party congress, "which will be a historic turning point in accomplishing the revolutionary cause of Juche," according to KCNA. 

Juche is the North's home-grown state ideology that combines Marxism and extreme nationalism established by the state founder and the current leader's grandfather, Kim Il Sung.

KCNA said Kim made the comments on a visit to the country's Ministry of the People's Armed Forces.

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SEOUL - A Canadian pastor serving a life sentence in North Korea for subversion said he spends eight hours a day digging holes at a labor camp, while a naturalized American citizen said he is being held by the state for spying, CNN reported from Pyongyang.

If confirmed, Kim Dong Chul, who CNN said was 60 and formerly of Fairfax, Virginia, would be the second Western citizen known to be held currently in North Korea. He was being held for spying for South Korea and asked the South or the U.S. government to rescue him, CNN said.

Hyeon Soo Lim, a South Korean-born Canadian who was the head pastor at one of Canada's largest churches, has been held by the North since last February. Lim, who was 60 at the time of his arrest, was sentenced to hard labor for life in December for attempting to overthrow the North's regime.

"I wasn't originally a laborer, so the labor was hard at first," Lim told CNN in Korean through an interpreter. "But now I've gotten used to it."

The charges against Lim lacked specifics, but he said it may be related to his open criticism of the North's three generations of leaders.

"I admit I've violated this government's authority, system and order," Lim said in the interview aired on Monday. Asked if his biggest crime was speaking badly of the North's leaders, he said: "Yes, I think so."

Lim was brought into a Pyongyang hotel for the interview, his hair cropped short and wearing a gray padded prison uniform bearing the number "036" on his chest. He said works eight hours a day, six days a week digging holes in an orchard at a labor camp where he has seen no other prisoners, CNN said.

Lim, who had lived in Canada since 1986, gets three meals and day and regular medical attention, CNN said. His church has said Lim had a "very serious health problem, very high blood pressure."

Lim had visited the North more than 100 times since 1997 and helped set up an orphanage and nursing home, according to the church.

In a separate interview, Kim told CNN he spied on behalf of "South Korean conservative elements" and was arrested in October.

"I was tasked with taking photos of military secrets and scandalous scenes," Kim said.

The U.S. embassy in Seoul said it was aware of the report but did not have further comment.

A U.S. State Department official declined to comment on the reports, saying that speaking publicly about specific cases of detained Americans can complicate efforts to get them released.

If confirmed, Kim would be the first American to be detained since the North released three U.S. citizens in 2014.

He said he had moved to the Chinese city of Yanji near the border with North Korea and worked in the North Korean city of Rason in a trading business, when a number of South Koreans approached him

"They asked me to help destroy the (North's) system and spread propaganda against the government," he said. He was being held at a Pyongyang hotel and was in good health, CNN said.

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North Korea on Saturday called for the conclusion of a peace treaty with the United States and a halt to U.S. military exercises with South Korea to end the North's nuclear tests.

The isolated state has long sought a peace treaty with the United States, as well as an end to the exercises by South Korea and the United States, which has about 28,500 troops based in South Korea.

"Still valid are all proposals for preserving peace and stability on the peninsula and in Northeast Asia including the ones for ceasing our nuclear test and the conclusion of a peace treaty in return for U.S. halt to joint military exercises," North Korea's official KCNA news agency cited a spokesman for the country's foreign ministry as saying early on Saturday.

The two Koreas remain in a technical state of war since their 1950-1953 conflict ended in a truce, not a peace treaty.

North Korea said on Jan. 6 it had tested a hydrogen bomb, provoking condemnation from its neighbors and the United States.

Experts have expressed doubt that the North's fourth nuclear test was of a hydrogen bomb, as the blast was roughly the same size as that from its previous test, of a less powerful atomic bomb, in 2013.

Pyongyang is under UN sanctions for its nuclear and missile programs.

(Reporting by Tony Munroe; editing by Andrew Roche)

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Kim Jong-Un is described as one of the world's scariest dictators. Here's how the  youngest leader in North Korea's history rose to power.

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North Korea claims it has invented hangover-free alcohol. The reclusive dictatorship says it has perfected a liquor that doesn't cause nasty after-effects.

A North Korean factory claims it has invented an alcohol that doesn't cause hangovers. Koryo liquor is between 30 and 40 percent proof but a new recipe will not cause headaches the morning after. In fact, the manufacturer claims the drink is good for you.

North Korea's Pyongyang Times proudly reported the invention in an article filled with florid language, claiming it "is highly appreciated by experts and lovers as it is suave and causes no hangover."

This is not the first time North Korea has made a big claim about a seemingly miraculous product. The isolated nation said last year it had invented a vaccine effective against HIV/AIDS, cancer and the Ebola virus, among other fantastic claims.

The hereditary dictatorship, currently ruled by third generation leader Kim Jong-Un, is no stranger to making huge claims that cannot be independently verified. It recently detonated a nuclear device that it claimed was its first hydrogen bomb. International observers said that while the new bomb was very powerful, it was most likely not a H-Bomb.

North Korea is famous for its propaganda, recently dropping leaflets on South Korea threatening their neighbors and calling the south's President Park Guen-hye a mad dog. The leaflets also featured a cartoon of Park in a red bikini and called her "human filth."

The official head of state in North Korea is Kim Il-sung, who died in 1994 but is still a part of North Korea's political mythology. Given the country's long history of outlandish claims, reports of a hangover-free spirit should be taken with caution.

It is unlikely that ordinary North Koreans will benefit from the invention as Koryo liquor is only available to the elite. Many North Koreans struggle to feed their families.

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SEOUL (Reuters) - North Korea has detained a U.S. university student, the third western citizen known to be held in the isolated state, for committing a "hostile act" and wanting to "destroy the country's unity", it said on Friday. 

Otto Frederick Warmbier, 21, of the University of Virginia, was in North Korea for a five-day New Year trip and was detained at Pyongyang airport on Jan. 2 ahead of a flight back to China, said Gareth Johnson of Young Pioneer Tours, which organized the visit.

According to the North's official KCNA news agency, Warmbier entered North Korea as a tourist and "was caught committing a hostile act against the state", which it said was "tolerated and manipulated by the U.S. government".

An official at the U.S. embassy in the South Korean capital Seoul said it was aware of the reported arrest. The U.S. State Department in Washington had no immediate comment.

Johnson said China-based Young Pioneer Tours was in contact with Warmbier's family and U.S. officials.

"We are in touch with Otto's family, the U.S. State Department and the Embassy of Sweden in Pyongyang and doing all we can to secure his release," Johnson told Reuters.

The Swedish Embassy represents U.S. interests in North Korea.

KCNA said Warmbier had entered the country with an "aim to destroy the country's unity". It did not elaborate.

According to his social media profiles, Warmbier is from Cincinnati and is an Echols Scholar, awarded to the top seven percent of incoming first year students at the University of Virginia, where he majors in economics with a minor in global sustainability.

Warmbier has also visited Cuba, Ireland and Israel, according to his Facebook profile.

Warmbier was detained four days before North Korea conducted its fourth nuclear test in violation of UN sanctions, which drew condemnation from its neighbors and the United States.

South Korea warned that the United States and its allies were working on further sanctions to inflict "bone-numbing pain" on North Korea after its latest nuclear test, and urged China to do its part to rein in its neighbor.

North Korea has a long history of detaining foreigners, and the U.S. and Canadian governments advise against travel there.

Pyongyang has in the past used detained U.S. citizens to extract high-profile visits from the United States, with which it has no formal diplomatic relations.

While the vast majority of tourists to North Korea are from China, roughly 6,000 westerners visit the country annually. Most are adventure-seekers curious about life behind the last sliver of the iron curtain, and ignore critics who say their dollars prop up a repressive regime.

Warmbier was on Young Pioneer's "New Year's Party Tour", which, according to the itinerary on the company's website, was to include watching fireworks in Kim Il Sung Square in the heart of Pyongyang, and an optional helicopter ride.

A South Korean-born Canadian pastor was arrested in North Korea last year and given a life sentence for subversion. Earlier this month, a Korean-American man told CNN in Pyongyang that he was being held by the state for spying.

In 2014, Pyongyang released three detained Americans. Last October, it freed a South Korean national with a U.S. green card after holding him for six months.

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North Korean defector and author of "The Girl With Seven Names" Hyeonseo Lee explains how she escaped the country and survived.

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