(ATTN: RECASTS headline, updates paras 1-6 with details on flight of B-52H; TRIMS)
SEOUL, Dec. 11 (Yonhap) -- The United States on Wednesday flew a Global Hawk surveillance plane over the Korean Peninsula and a strategic B-52 bomber over the sea near Japan, an aviation tracker said, amid brewing tensions over Pyongyang's threat of possible military provocations.
A Stratofortress, supported by a KC-135R refueling aircraft, was spotted in skies above Japan's east, Aircraft Spots said on its Twitter account without specifying the exact time of the operation.
It said the aircraft took off from Andersen Air Force Base in Guam.
Earlier in the day, the U.S. Air Force sent an RQ-4 Global Hawk over the Korean Peninsula, according to the tracker.
The flights came as tensions have heightened since Pyongyang conducted a rocket engine test at its Dongchang-ri satellite launching site on Saturday, sparking speculation that it may be preparing to resume testing of intercontinental ballistic missiles.
North Korea has been ramping up pressure on the United States, stressing that the year-end deadline Pyongyang has set for Washington to come up with a new proposal in their nuclear negotiations is drawing near.
The B-52H, a long-range and large-payload multirole bomber, is one of the U.S. Air Force's principal strategic assets.
Global Hawk is a high-altitude long-endurance unmanned aerial vehicle capable of performing reconnaissance missions in the air for more than 30 hours at a time. It is considered one of the most advanced intelligence-gathering platforms in the world.
In recent weeks, the U.S. has deployed several types of surveillance planes over the peninsula, including its Navy's P-3C maritime surveillance plane, the RC-135U Combat Sent, the RC-135W Rivet Joint, the RC-135S Cobra Ball aircraft and the E-8C aircraft.
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