Despite the hostile language, the North Koreans went ahead on Thursday with what they described as the dismantlement of their nuclear test site.
North Korea allowed a select group of journalists from Britain, China, Russia, South Korea and the United States to watch its engineers destroy and close tunnels in its mountainous Punggye-ri test site, where the country has conducted all six of its nuclear tests. No independent outside nuclear monitors were invited to verify the dismantlement of the site.
In the ceremony on Thursday, North Korea detonated explosives inside three of its four tunnels at the Punggye-ri test site, according to dispatches by reporters at the scene. The fourth tunnel had already been closed for fear of contamination after the North’s first nuclear test in 2006.
The North Koreans also blew up test-observation facilities, as well as barracks for site personnel and a metal foundry, the reports said. Two dozen international journalists were invited to witness explosives rigged inside the tunnels, and they were then escorted outside to viewing decks 500 yards away, where they filmed the detonations.
North Korea invited mostly TV journalists to ensure that its action would be broadcast worldwide.
Some analysts feared the moves would be reversible — as when the North disabled and then restarted a nuclear reactor years ago. But Thursday’s reported demolition at the test site was the first concrete step North Korea has taken toward what Washington had been hoping would be a complete nuclear dismantlement under Mr. Kim.