Not a bomb

last updated 8 January 2015

Yongjori, North Korea

A mushroom cloud that appeared over North Korea last week was not the result of a nuclear bomb test, North Korean officials said this week. The explosion set off alarms in intelligence circles around the world. But no radiation was detected, and U.S. and South Korean officials said they found no evidence of nuclear material. The government in Pyongyang said it had set off a massive conventional explosion to level a mountain and clear the way for a hydroelectric dam. Western nuclear experts said the blast might actually have been an accidental explosion at an arms depot, since it occurred just a few miles from a North Korean military base.