The chief of South Korea's weather agency said Monday that should North Korea detonate another nuclear device, it could trigger a collapse of its mountainous test site and a leak of radioactive materials.

Nam Jae-cheol, the chief of the Korea Meteorological Administration, made the remarks during a parliamentary audit amid reports over a possible implosion at the Punggye-ri site in the North's northeastern region where it has carried out six nuke tests since 2006.

"Based on our analysis of satellite imagery, we judge that there is a hollow space, which measures about 60 to 100 meters (in length), at the bottom of Mount Mantap in the Punggye-ri site," he said. "So, should another nuke test occur, there is the possibility (of a collapse)."

Asked if an earthquake would trigger a release of radioactive materials, Nam said, "Should it sink, there is a possibility."

On Friday, the Hong Kong-based newspaper South China Morning Post reported that Chinese geologists warned a North Korean delegation last month of a possible implosion at the North's nuclear test facility.

It also said that a day after the North conducted its sixth and most powerful nuke test on Sept. 3, a senior Chinese nuclear scientist said additional tests could blow the top off the mountain in the test site, and that radioactive waste could come out from the cracks. (Yonhap)