Early evidence around North Korea's use of a bomb suggest that it may have been a "boosted" nuclear device — more powerful than what it's detonated before but far less dangerous than an H-bomb.
NBC News reports that it will take a couple of days for the U.S. to determine verify North Korea's claim that it detonated a hydrogen bomb.
Seismic data from Tuesday night's event would have shown a much greater force yield if hydrogen was involved, experts said. Instead, it was identical to the data collected after North Korea's tests in 2006, 2009 and 2013.
U.S. & World
Air samples collected by drone should soon give analysts an idea of what happened, a senior U.S. military official said. But for the moment, the North Korean boast is being treated with skepticism.