The Japanese Defense Ministry says it is tracking what officials have described as “unusual” military air activity by China near Japan’s airspace.

According to new data released by the defense ministry, “unusual” flights by China’s People’s Liberation Army Air Force (PLAAF) near Japanese airspace increased in the first half of the 2017 fiscal year. The flights included never-before-seen levels of PLAAF exercises and drills held in international air lanes near Japan’s first island chain, including the Miyako Strait.

In addition, the defense ministry noted the increased presence of Chinese unmanned aerial vehicles (UAVs) in the East China Sea, where Tokyo and Beijing have long-running territorial disputes regarding the Senkaku Islands, currently administered by Japan but claimed as the Diaoyu Islands by China.

China has based its BZK-005on Daishan Island in Hangzhou Bay near Shanghai since at least 2015 to facilitate surveillance of the East China Sea.

Per the new data released by the Japanese Ministry of Defense, the JASDF also scrambled 561 times in response to aircraft. This number was slightly lower than the record-setting figures released last year, but is greater than figures for this period in any year except 2016.

Per data released in April 2017, the JASDF scrambled jets 1,168 times in 2016, up from 873 in 2015, in response to Chinese jets. In recent years, more JASDF fighters have scrambled to meet Chinese aircraft than Russian aircraft, which used to trigger the most responses from Japan’s air forces.

Analyst comment: The disputed islands are the biggest potential flashpoint for a potential Japan-China conflict in the future.

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