This is an article from www.wsj.com:
YONGBYON, North Korea -- North Korea destroyed the most visible symbol of its nuclear weapons program Friday in a sign of its commitment to stop making plutonium for atomic bombs.
|Watch as North Korea blows up a cooling tower at a controversial nuclear plant. The move was largely symbolic, as the U.S. ratcheted down sanctions against the country. (June 27)|
The demolition of the 60-foot-tall cooling tower at the North's main reactor complex is a response to U.S. concessions after the North delivered a declaration Thursday of its nuclear programs to be dismantled.
The tower exploded in a single blast, sending a puff of gray smoke into the air, according to video footage filmed by broadcaster APTN at the site.
The symbolic explosion came just 20 months after Pyongyang shocked the world by detonating a nuclear bomb in an underground test to confirm its status as an atomic power. The nuclear blast spurred an about-face in the U.S. hard-line policy against Pyongyang, leading to the North's first steps to scale back its nuclear weapons development since the reactor became operational in 1986.