North Korea tested a hydrogen bomb earlier this month.North Korea on September 3 announced it had conducted a "successful" hydrogen bomb test, hours after two tremors were detected in the country.
"The hydrogen bomb test was a perfect success," North Korean state television
... and if you can't believe state television who can you believe?
said, adding that the device was capable of being loaded onto long-range missiles.
The United States had previously declined to characterize the test.