U.S. and international nuclear experts had estimated that the latest
test was in the 3- to 4-kiloton range. Former nuclear weapons inspector
David Albright,
the director of the Institute for Science and International Security,
said the test shows that the North Koreans are “pushing their program
along” and that they have “made progress.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.In its confirmAt a news briefing on Monday, State Department
Spokesman Ian Kelly called on Pyongyang to end its bellicose threats
and return to Chinese-sponsored six-party negotiations on its nuclear
program.