WASHINGTON, Jan 28 (Reuters) - North Korea might have attempted to test components of a hydrogen bomb earlier this month, CNN reported on Thursday, citing an unnamed U.S. official.
North Korea tested a nuclear device on Jan. 6 that it said was a hydrogen bomb.
A U.S. official directly familiar with the latest U.S. assessment said the explosion may have been a partial, failed test of some type of components associated with a hydrogen bomb, CNN reported.
Click through images from North Korea's Punggye-ri Nuclear facility:
The size of the seismic event and other intelligence indicate it was not likely a fully functioning device, CNN said.
The official said it is possible the North Koreans believe they conducted a full hydrogen bomb test, but the U.S. believes it was likely only some components, perhaps a detonator, that exploded, CNN reported.
U.S. State Department spokesman Mark Toner told reporters earlier on Thursday that the United States still believes that Pyongyang did not test a hydrogen bomb.
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