Norks blow up nuclear test tunnels?

BBC:

North Korea appears to have blown up tunnels at its only nuclear test site, in a move to reduce regional tensions.

Foreign journalists at the Punggye-ri nuclear testing site in the north-east said they witnessed a huge explosion.

Pyongyang offered to scrap the site earlier this year as part of a diplomatic rapprochement with South Korea and the US.

But scientists believe it partially collapsed after the last test in September 2017, rendering it unusable.

Independent inspectors were not allowed to witness the process of the dismantling of the Punggye-ri site in the mountainous region of the country, and some worry it could be easily reversible, the BBC's Laura Bicker reports.
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Three tunnels were collapsed in a series of explosions in front of about 20 handpicked international journalists.

Two blasts were reportedly carried out in the morning, and four in the afternoon.

Sky News' Tom Cheshire was among the journalists present. He said the doors to the tunnels were "theatrically rigged" with "wires everywhere".

"We hiked up into the mountains and watched the detonation from about 500m away (550 yards)," he was quoted by Sky News as saying.
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The Comprehensive Nuclear Test Ban Treaty Organisation (CTBTO) could have confirmed that the test site is no longer capable of conducting nuclear tests - but experts from the UN-backed monitoring group were not invited to Thursday's dismantling of Punggye-ri.
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It will take more than these explosions to confirm that North Korea has abandoned its nuclear ambitions.  Its refusal to allow inspectors on the site could mean the explosions wer3e just for show and that the damaged site was not worth saving.   It does not mean that they do not have an alternative site.

One of the ways the Trump administration could test their sincerity would be to get details from North Korea about its cooperation with Iran.