North Koreans have made nuclear progress, experts say Posted byadmin June 16, 2009 The U.S. intelligence community believes that North Korea tested a nuclear device last month with an explosive yield of several kilotons, considerably more powerful than its first test nearly three years ago. Related posts: U.S. tries again on North Korean nuclear talks Iran president ‘proud’ of nuclear progress North Korea’s reported nuclear test no surprise, Mullen says Obama: North Korean nuclear test ‘a grave threat’ N. Korea to let stranded S. Koreans cross