"The republic's first hydrogen bomb test has been successfully performed."

State-controlled media in North Korea is stating tonight that the nation has successfully tested its first hydrogen bomb. The reports are corroborated by seismic activity from the nuclear test site. The BBC reports:

State media announced the test after monitors detected a 5.1 magnitude quake close to the Punggye-ri site.

The North is thought to have conducted three previous underground nuclear tests there since 2006.

A hydrogen bomb uses fusion to create a blast far more powerful than that of a more basic atomic bomb.

In a surprise announcement a newsreader on North Korean state TV said: "The republic's first hydrogen bomb test has been successfully performed at 10:00 am on January 6, 2016."

CNN has additional reporting, including this gem from the state media:

"If there's no invasion on our sovereignty we will not use nuclear weapon," the North Korean state news agency said. "This H-bomb test brings us to a higher level of nuclear power."

Note that the previous three bombs were fission, whereas this one is (reportedly) fusion. It will take some time for officials in the United States and South Korea to verify the claim, but for intelligence and defense agencies, there can be little doubt that this will be treated as a legitimate claim. As CNN noted in their on-air reporting, the pattern matches the previous tests almost exactly.

TruthRevolt will update this story as information becomes available.

Update: State Department issues statement.