By CNN Staff
China scrambled some of its fighter jets Friday morning to identify U.S. and Japanese military aircraft that entered its newly declared air defense zone over the East China Sea, China's state-run Xinhua news agency reported, citing the Chinese military.
There was no immediate confirmation from the U.S. or Japanese governments. If true, it could be the latest challenge to the zone by nations including the United States, which earlier in the week defied China's demand that planes flying there identify themselves.
China declared the air defense identification zone -- a unilaterally imposed buffer zone outside a country's sovereign airspace -- last weekend. It's part of a rapidly escalating dispute over contested territory in and above the East China Sea, as it overlaps similar zones claimed by neighboring countries and covers islands claimed by both China and Japan.
Two U.S. surveillance aircraft and 10 Japanese planes, including surveillance and combat aircraft, flew into the zone, Chinese military representative Lt. Shen Jinke said Friday, according to Xinhua.
The Chinese jets identified and monitored the U.S. and Japanese planes, Jinke said. No incidents between the aircraft were reported.
A dismissal of the zone wouldn't be the first this week. Two U.S. B-52 bombers passed uncontested through the zone without altering China on Monday, in what the Pentagon described as a preplanned military exercise.
South Korea also said its military sent a plane on a routine patrol flight into the zone without telling China on Tuesday. A South Korean Defense Ministry official said such flights are carried out twice a week, and would continue despite China's ADIZ declaration.
Japan also signaled its rejection of Beijing's move Thursday, with Chief Cabinet Secretary Yoshihide Suga telling reporters his country's Self Defense Force continued surveillance patrols of disputed territory in the East China Sea just as it had before China's declaration.
Two major Japanese airlines have already refused to comply with China's declaration.
CNN's Jason Hanna, Tim Hume, Jethro Mullen and Yoko Wakatsuki contributed to this report.
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