Japan has regularly scrambled its jets to escort Chinese aircraft approaching close to national airspace in 2018, with a previous incident taking place on 14 December and the overall number of intercepts reaching 7 in just the last half of this year.

Japan's Air Self-Defence Force intercepted a Chinese Shaanxi Y-9JB spy plane capable of conducting electronic warfare on 27 December as it was crossing the East China Sea and Tsushima Strait, a channel, which lies between Korea and Japan, The Diplomat reported, citing Japan's Ministry of Defence. The plane reportedly didn't enter Japan's airspace, but was still intercepted and escorted by the Japanese jets.

Chinese officials have not commented on the report.

This was the seventh time the country's Air Self-Defence Force was put on high alert by approaching Chinese spy planes in the last six months with the previous time taking place on 14 December. In each of the cases, the Chinese planes stayed in international airspace.

The two states are currently engaged in a territorial dispute over the uninhabited Senkaku/Diaoyu islands in the East China Sea with both countries claiming sovereignty over them. Japan claims the islands belong to them under the 1971 Okinawa reversion deal, while China argues the islands have belonged to it since ancient times.

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In 2013 the latter unilaterally established air-defence identification zone, demanding all aircraft flying over the islands to present flight plans and identification of the transponder. The move has intensified tensions between Tokyo and Beijing.