"In connection to the Chinese military plane entering today the Korean anti-aircraft radar zone, the head of the Department of International Policy of the Defense Ministry, having summoned today in the afternoon Chinese military attache, expressed a strong protest and insisted that measures should put in place to avoid the repetition of such incidents," the ministry said in a press release.
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According to local media reports, China's Shaanxi Y transport aircraft entered the South Korean anti-aircraft radar zone without warning and spent four hours there.
About 10 F-15K fighter aircraft were scrambled in response to the Chinese plane.
The incident took place near Socotra Rock.