By Associated Press Reporter PUBLISHED: 23:50 EST, 28 November 2013 | UPDATED: 23:50 EST, 28 November 2013 China said it sent warplanes into its newly declared maritime air defense zone days after the U.S., South Korea and Japan all sent flights through the airspace in defiance of rules Beijing says it has imposed in the East China Sea. China's air force on Thursday sent several fighter jets and an early warning aircraft on normal air patrols in the zone, the Xinhua agency reported, citing air force spokesman Shen Jinke. The report did not specify exactly when the flights were sent or whether they had encountered foreign aircraft. The United States, Japan and South Korea have said they have sent flights through the zone without encountering any Chinese response since Beijing announced the creation of the zone last week.
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China announced it would impose rules in the airspace above the East China Sea
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The US, Japan and South Korea all sent planes through the zone after the announcement with no action from China
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China has now sent warplanes into the zone to protect the airspace
Without prior notice, Beijing began demanding Saturday that passing aircraft identify themselves and accept @placeholder instructions or face consequences in an East China Sea zone that overlaps a similar air defense identification zone overseen by Japan since 1969 and initially part of one set up by the U.S. military.