North Korea demolishes nuclear test site, as Trump cancels summit with Kim Jong Un

Thomas Maresca | USA TODAY

Show Caption Hide Caption North Korea calls VP Pence a ‘political dummy' North Korea going after the Vice President of the United States…threatening to back out of their upcoming summit with the U.S. Veuer's Nick Cardona has that story.

SEOUL — North Korea demolished its nuclear test site in a step toward denuclearization Thursday, even as President Trump canceled what would have been a landmark summit with North Korean leader Kim Jong Un planned for next month.

At least three tunnels as well as other structures at the Punggye-ri nuclear test site in the mountainous northeast of the country were destroyed by five explosions over the course of several hours Thursday, South Korean journalists reported. All six of the reclusive nation’s nuclear tests have been held at the site.

The demolition was announced by Kim ahead of what would have been the first meeting between a sitting U.S. president and a North Korean leader that was planned for June 12 in Singapore.

Hours after the nuclear site demolition, the White House released a letter Thursday from Trump to Kim saying that the meeting would not go ahead.

"I was very much looking forward to being there with you. Sadly, based on the tremendous anger and open hostility displayed in your most recent statement, I feel it is inappropriate, at this time, to have this long-planned meeting," the letter read.

"Therefore, please let this letter serve to represent that the Singapore summit, for the good of both parties, but to the detriment of the world, will not take place. You talk about your nuclear capabilities, but ours are so massive and powerful that I pray to God they will never have to be used."

More: Trump cancels meeting with North Korea, citing 'tremendous anger and open hostility'

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The developments came after a top North Korean official launched a blistering verbal assault on Vice President Mike Pence, calling his recent remarks comparing the reclusive nation with Libya “ignorant” and “stupid.”

North Korean Vice Foreign Affairs Minister Choe Son Hui made the remarks, according to the North’s official Korean Central News Agency, after Pence said North Korea could end up like Libya if it doesn’t make a nuclear deal with Washington.

"As a person involved in U.S. affairs, I cannot suppress my surprise at such ignorant and stupid remarks gushing from the mouth of the U.S. vice president," Choe said, according to KCNA.

Trump had cast new uncertainty Tuesday on the planned summit, saying the date could slide back on the calendar — or it may not happen at all.

Questions remain about demolishing of nuclear test site

At the Punggye-ri nuclear test site Thursday, South Korean journalists reported the first explosion for the demolition occurred at 11 a.m. local time, and the final blasts ended at 4:17 p.m..

A group of international journalists from the U.S., U.K., Russia, China and South Korea were invited to observe the dismantling. They had no Internet access while on the site.

No technical experts were believed to be on site Thursday, raising questions about how complete and irreversible the destruction is. North Korea held a closing ceremony afterward with officials from its nuclear arms program in attendance.

Sadly, I was forced to cancel the Summit Meeting in Singapore with Kim Jung Un. pic.twitter.com/qEoi9ymUEz — Donald J. Trump (@realDonaldTrump) May 24, 2018

“The dismantling of the nuclear test ground conducted with high-level transparency has clearly attested once again to the proactive and peace-loving efforts of the DPRK government being made for assuring peace and stability on the Korean Peninsula and over the world,” the KCNA reported, using the North's formal name, the Democratic People’s Republic of Korea.

Seoul welcomed the demolition of the nuclear test site as a step forward in the process of denuclearizing the Korean Peninsula, which the two Koreas agreed upon as a goal after a summit between Kim and South Korean President Moon Jae-in.

“We expect that this measure will be a chance for a complete denuclearization in the future,” Noh Kyu-duk, spokesman for the Ministry of Foreign Affairs, told reporters Thursday.

The demolition was also generally well-received by nuclear arms control experts.

“In the wake of what increasingly seems like unhelpful rhetoric from (the U.S. and North Korea) over the last week, the destruction today is a welcome goodwill gesture in advance of a possible summit,” said Alexandra Bell, senior policy director at Washington D.C.-based Center for Arms Control & Non-Proliferation.

She warned the demolition doesn’t mean that North Korea couldn’t decide to conduct further tests.

“They can always decide to dig new tunnels (at Punggye-ri) even if they've exploded or collapsed the ones they used before,” she added. “They can always test elsewhere."

More: North Korea prepares to dismantle nuclear test site

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The Libyan model controversy

Pence compared North Korea to Libya in an interview with Fox News on Monday.

"There was some talk about the Libyan model last week, and you know, as the President made clear, this will only end like the Libyan model ended if Kim Jong Un doesn't make a deal," Pence said in the interview.

When told his statement could be interpreted as a threat, he said: "Well, I think it's more of a fact."

Libyan dictator Moammar Gadhafi gave up his nuclear program in a deal with the U.S. and Britain in the early 2000s, but was overthrown and brutally killed by Washington-backed rebels in 2011.

Pyongyang had threatened to reconsider the summit if the Trump administration pressures North Korea to unilaterally abandon its nuclear weapons.

The North said before the White House cancelled the summit that a nuclear showdown with the U.S. could once again be possible, reverting to Pyongyang's rhetoric before the recent moves toward diplomacy.

“We will neither beg the U.S. for dialogue nor take the trouble to persuade them if they do not want to sit together with us,” Choe said, KCNA reported.

“Whether the U.S. will meet us at a meeting room or encounter us at nuclear-to-nuclear showdown is entirely dependent upon the decision and behavior of the United States,” she added.

Contributing: Jane Onyanga-Omara in London; The Associated Press.