Seoul, Feb 16 (IANS): The US has deployed four B-52 nuclear-capable bombers to Guam to demonstrate America's "commitment to the region," its military said on Wednesday, amid concerns that Pyongyang could conduct provocative acts in time for key political events.

The US Pacific Air Force said the bombers and more than 220 Air Force personnel have arrived at Andersen Air Force Base on the Pacific Island to support training efforts with allies and partners, Yonhap news agency reported.

Speculation has lingered that Pyongyang could stage another show of force to mark the 80th birthday of his late father, Kim Jong-il, on Wednesday and the 110th birthday of his late grandfather Kim Il-sung on April 15.

The late leader's birthday this week has, so far, been largely uneventful, with the North's state media highlighting his legacies, such as improvement in the country's ties with China.

The US military said the arrival of the bombers demonstrates the US' security commitment to the Indo-Pacific region.

"Put simply, we are here to support a stable, secure, and free Indo-Pacific region," Lt Col. Christopher Coleman, the commander of the 96th Expeditionary Bomb Squadron, was quoted as saying.

Last month, Pyongyang ratcheted up tensions with seven known rounds of missile launches, including the test of an intermediate-range ballistic missile capable of targeting Guam.

Meanwhile, the US Air Force was also said to have flown an RC-135V surveillance jet over the greater Seoul area on Wednesday, possibly to monitor activities in the North on Kim Jong-il's birthday.