Two U.S. military aircraft flew into China's newly claimed and challenged air defense zone over the East China Sea, a U.S. official said, an action that could inflame tensions between the world powers. The U.S. Air Force B-52 planes -- which were not armed because they were on a training mission -- set off Monday from Guam and returned there without incident. The mission lasted for several hours, and the aircraft were in China's newly declared air zone for about an hour, according to the U.S. official. The planes' pilots did not identify themselves upon entering the disputed airspace, as China would have wanted, according to the official.
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Japanese airlines say they will not submit flight plans to China for the zone
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Chinese ambassador: It's "the right of every country to defend its airspace"
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U.S. calls the move an apparent try "to unilaterally change the status quo"
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U.S. official: B-52s don't tell Beijing about flight over China's new air defense zone
The @placeholder government has rallied around its ally Japan, where thousands of its troops are stationed as part of a security treaty.
In December 2012, the dispute escalated further when Japan scrambled fighter jets after a @placeholder plane was seen near the islands.