Story highlights US bomber flyover was a response to North Korea's nuclear test

North Korea says US using flyovers in plan to launch pre-emptive attack

(CNN) North Korea on Wednesday scoffed at the US Air Force's show of force a day earlier, saying Washington was "bluffing" and "blustering" with the flyover of B-1 bombers.

"They are bluffing that B-1Bs are enough for fighting an all-out nuclear war," said a statement from Pyongyang's Korean Central News Agency.

Two of the powerful US bombers, joined by US and South Korean fighter jets, flew over Osan Air Base south of Seoul on Tuesday to show US anger with North Korea's nuclear weapons test four days earlier.

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Pyongyang claimed Friday's test showed it had a nuclear warhead that could be mounted on ballistic missiles, a possibility that increases fears for US allies in the region and also poses a threat to US bases in South Korea, Japan and Guam.

The US commander in South Korea, Gen. Vincent K. Brooks, called the North's nuclear test "a dangerous escalation" and "an unacceptable threat."

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