The latest on North Korea's announcement that it conducted a hydrogen bomb test last week (all times local):


12:45 p.m.

A U.S. B-52 bomber has returned to its base on the Pacific island of Guam after flying over South Korea following North Korea's nuclear test.

The U.S. military's Pacific Command says in a statement that the bomber was joined by South Korean F-15 and U.S. F-16 fighters in the fly-over show of force.

Adm. Harry B. Harris Jr., commander U.S. Pacific Command, says: "This was a demonstration of the ironclad U.S. commitment to our allies in South Korea, in Japan, and to the defense of the American homeland."

He adds: "North Korea's nuclear test is a blatant violation of its international obligations."


12:15 p.m.

A powerful U.S. B-52 bomber has flown over South Korea in a show of force following North Korea's fourth nuclear test.

The long-range bomber, which is capable of delivering nuclear weapons, could be seen flying Sunday over Osan Air Force Base south of Seoul.

North Korea will likely see the landing as a threat.

Any hint of American nuclear power enrages Pyongyang, which links its own pursuit of atomic weapons to what it sees as past nuclear-backed moves by the United States to topple its authoritarian government.

After North Korea's third nuclear test in 2013, the U.S. also sent its most powerful warplanes to drills with South Korea.

— Foster Klug, Seoul