As close to known fact as you can get without inspecting the site in person. It started with warnings from Chinese geologists last fall [1], was followed by uno

As close to known fact as you can get without inspecting the site in person. It started with warnings from Chinese geologists last fall [1], was followed by unofficial news of a partial collapse which left 200 tunnel workers dead [2][3], and then by papers by two different groups concluding that the site has collapsed [4]. [1] http://www.scmp.com/news/china/society/article/2117340/chinese-scientists-warn-north-korea-about-disaster-threat-nuclear http://www.scmp.com/news/china/society/article/2117340/chine... [2] https://www.express.co.uk/news/world/873443/north-korea-nuclear-accident-Punggye-ri-tunnel-collapse-kim-jong-un https://www.express.co.uk/news/world/873443/north-korea-nucl... [3] https://www.bloomberg.com/news/articles/2017-11-01/about-200-died-at-north-korea-nuclear-site-tv-asahi-reports https://www.bloomberg.com/news/articles/2017-11-01/about-200... [4] http://www.bbc.com/news/world-asia-43894394 http://www.bbc.com/news/world-asia-43894394