North Korean leader Kim Jong Un attends a ceremony to award party and state commendations to nuclear scientists, technicians, soldier-builders, workers and officials for their contribution to what North Korea said was a succesful hydrogen bomb test, at the meeting hall of the Central Committee of the Workers' Party of Korea (WPK) in this undated file photo released by North Korea's Korean Central News Agency (KCNA) on January 13, 2016. REUTERS/KCNA/Files

WASHINGTON (Reuters) - North Korea might have attempted to test components of a hydrogen bomb on Jan. 6, 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.

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.

(This version of the story corrects to show components possibly tested on Jan. 6)