China on Friday sent fighter jets to monitor US and Japanese military aircraft flying in its new air-defense zone over the East China Sea, state media reported.
Beijing announced a week ago that all aircraft entering the zone, which covers territory claimed by China, Japan, Taiwan and South Korea, must submit flight plans and identify themselves to Chinese authorities or face unspecified “defensive emergency measures.”
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The US, Japan and South Korea have vowed to ignore China’s demands, and accused Beijing of unnecessarily raising tensions in the region. All three countries have sent military aircraft into the area in recent days.
On Saturday, the US cautioned its civilian aircraft, saying in a statement that it expected these planes to follow China's new air defense rules.
The State Department said this "does not indicate US government acceptance of China's requirements for operating in the newly declared Air Defense Identification Zone."
CNN reported that United, American and Delta airlines confirmed on Saturday that its pilots were following Washington's advice.
On Friday, the People’s Liberation Army Air Force spokesman Shen Jinke said Chinese warplanes had been scrambled in an “emergency response to verify two reconnaissance aircraft from the United States and indentify 10 Japanese planes,” the official Xinhua news agency reported.
"The PLA air force has realized its effective normal monitoring of targets in the zone," Shen said.
That followed state media reports on Thursday that said China had sent aircraft into the contested zone following Japanese and South Korean incursions.
The air-defense zone is seen as an attempt by Beijing to solidify its claim to a group of Japanese-administered islands, which are known as Diaoyu in Chinese and Senkaku in Japanese.
But governments and experts worry that the zone raises the risk of the current war of words spilling over into a full-blown conflict in the event of a military or political misstep.
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