North Korea claimed it detonated a hydrogen bomb in a test Wednesday, a move that was condemned by the U.S., Britain, Japan and even China. It was the politically isolated country's first nuclear weapons test explosion in three years.
Experts said the claim that the test involved a hydrogen bomb, which is more powerful than an atomic bomb, could not be confirmed. The White House said that initial analysis of the test was not consistent with a successful hydrogen bomb.
The report on the state KCNA website came within hours of reports from various agencies that a large earthquake had been detected near a known North Korean nuclear test site.
According to KCNA, North Korea tested a miniaturized hydrogen nuclear bomb "in the most perfect manner," putting it in possession of hydrogen bomb capability, which it described as "the most powerful nuclear deterrent."
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North Korea wanted what it called "the H-bomb of justice" as protection from the "ever-growing nuclear threat and blackmail by the U.S.-led hostile forces," according to KCNA.
It would use the weapons only if its sovereignty were encroached upon, the statement on KCNA said, but would not roll back its nuclear development until the U.S. had dropped its "vicious, hostile" policy toward the isolated Communist state.
"The U.S. is a gang of cruel robbers which has worked hard to bring even a nuclear disaster to the DPRK [Democratic People's Republic of Korean], not content with having imposed the thrice-cursed and unheard-of political isolation, economic blockade and military pressure on it for the mere reason that it has differing ideology and social system," according to the statement.
"The present-day grim reality clearly proves once again the immutable truth that one's destiny should be defended by one's own efforts," the statement went on. "Nothing is more foolish than dropping a hunting gun before herds of ferocious wolves."
It was North Korea's first nuclear test since February 2013 and the fourth overall.