Description:After launching its third successful nuclear test, North Korea honours nuclear developers in a musical tribute. The song, "At a burst", was shown by state KRT broadcaster as the country's scientists, technicians and officials visited Pyongyang Wednesday at the invitation of leader Kim Jong-un. On February 12, the state said it had successfully tested a miniaturised nuclear device, but U.S. and allied intelligence have yet to find particle traces to confirm the nature of the explosive.(1:09)