Source:
Reuters Japan scrambled fighter jets on Thursday after a Chinese government plane entered what Japan considers its airspace over disputed islets in the East China Sea, escalating tension between Asia's two biggest economies.
Japan protested to China over the incident but China brushed the complaint off saying the flight by the Chinese aircraft was "completely normal".
Sino-Japanese relations took a tumble in September after Japan bought the tiny islands, called Senkaku in Japan and Diaoyu in China, from a private Japanese owner.
Patrol ships from the two countries have been shadowing each other since then in a standoff that has raised concern that a collision could escalate into a clash. Thursday's incident was the first time both sides used aircraft in the dispute.
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http://uk.reuters.com/article/2012/12/13/uk-china-japan-scramble-idUKBRE8BC0HX20121213