- Satellite images taken Saturday show North Korea rebuilding its long-range-missile test site in Sohae, analysts say.
- The images were taken days after a summit between North Korean leader Kim Jong Un and US President Donald Trump ended in failure.
- North Korea started taking the site apart after Trump and Kim met in Singapore last year.
- Analysts have suggested that some rebuilding was already underway before last week's summit.
- The White House national security adviser, John Bolton, on Tuesday night said North Korea could face harsher sanctions if there was not progress on denuclearization.
Satellite images taken just after the collapse of last week's summit between President Donald Trump and Kim Jong Un show North Korea rebuilding a long-range-missile test site it pledged to dismantle, experts say.
The photographs are from Saturday, two days after Trump's meeting with Kim ended without agreement on the nuclear disarmament of North Korea.
They show North Korea rebuilding its long-range-rocket site at Sohae, according to analysts from the Center for Strategic and International Studies.
Previously, the Tongchang-ri facility had been used for satellite launches using missile technology North Korea is banned from using by the UN, the analysts said.
A South Korean lawmaker who was present at a closed-door briefing by South Korean intelligence Tuesday told the Associated Press that the structures being restored at the site included roofs and building doors.
The lawmaker said the National Intelligence Service director, Suh Hoon, told them that North Korea could be preparing to restart tests of long-range missiles if talks with Washington conclusively collapsed.
He suggested that another possibility was that the site could be dramatically blown up in a display of commitment to denuclearization if talks with the US resulted in a deal.
North Korea had begun to dismantle the facility following an agreement reached at June's Singapore summit between Trump and Kim, and it had been dormant since last August, experts say.
According to the monitoring website 38 North, efforts to rebuild structures at the site began between February 16 and March 2. Trump's summit with Kim began February 27.
Its experts say the images show the rail-mounted processing building, where launch vehicles are worked on before being moved to the launch pad, are being rebuilt.
They also identified support cranes, new roofs, and an engine support structure being developed at the test stand.
In a Fox News interview Tuesday night, the White House national security adviser, John Bolton, warned that new sanctions could be imposed on North Korea if the country did not further commit to denuclearization.
"If they're not willing to do it, then I think President Trump has been very clear," he said.
"They're not going to get relief from the crushing economic sanctions that have been imposed on them, and we'll look at ramping those sanctions up in fact."
Sanctions on North Korea are already restrictive, but experts at the conservative-leaning Heritage Foundation believe there is room for tougher measures to be imposed on Chinese financial entities accused of aiding North Korea's missile and nuclear programs.
The Council on Foreign Relations has argued that the existing sanctions regime requires better enforcement if it is to be effective.
Join the conversation about this story »
NOW WATCH: The wives of high-level cocaine traffickers reveal how their husbands took down 'El Chapo'