REUTERS
A tunnel under construction at North Korea's nuclear test site collapsed and as many as 200 workers could have been killed, a Japanese news report said Tuesday, according to South Korea's Yonhap News Agency.
About 100 people were trapped inside when the unfinished tunnel at the North's Punggye-ri nuclear test site collapsed, and an additional 100 people could have been killed while trying to rescue those trapped as a second collapse occurred, Japan's TV Asahi reported, Yonhap News Agency wrote.
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Experts have warned that the North's nuclear test site must have become fatigued and unstable from six nuclear tests, including last month's latest and most powerful one, that a collapse could happen at any time.
On Monday, the chief of South Korea's weather agency Korea Meteorological Administration, Nam Jae-cheol, said during a parliamentary meeting that another nuclear blast could trigger a collapse of the North's mountainous test site and a leak of radioactive materials.