SEOUL, South Korea (AP) – North Korea says it has conducted a hydrogen bomb test. The surprise announcement that complicates already difficult efforts to curb the country’s push for a working nuclear ...

SEOUL, South Korea — North Korea says it has conducted a hydrogen bomb test. The surprise announcement that complicates already difficult efforts to curb the country's push for a working nuclear ...

The test likely pushed Pyongyang's scientists and engineers closer to their goal of building a warhead small enough to place on a missile that can reach the U.S. mainland. But South Korea's spy agency ...

The UN Security Council has tentatively set an emergency meeting after North Korea’s H-bomb test.2:10 p.m. Crowds dressed in thick winter coats have gathered outside a large video screen near a ...

SEOUL, South Korea — The White House said today that initial data from its monitoring stations in Asia were “not consistent” with North Korea’s claim that the nuclear test it carried out earlier in ...

SEOUL (Reuters) - North Korea said it successfully tested a miniaturised hydrogen nuclear bomb on Wednesday, prompting scepticism among experts and officials who doubt Pyongyang has achieved such a ...

TOKYO -- North Korea announced it detonated a thermonuclear device Sunday in its sixth and most powerful nuclear test to date, a big step toward its goal of developing nuclear weapons capable of ...

SEOUL/WASHINGTON (Reuters) - North Korea on Sunday conducted its sixth and most powerful nuclear test, which it said was of an advanced hydrogen bomb for a long-range missile, prompting the threat of ...

Richard Garwin’s role in designing the hydrogen bomb was obscured from the public, even his family, as he advised presidents and devoted his life to undoing the danger he created. Richard L. Garwin, ...