BEIJING, China — More than 40 Chinese warplanes crossed a strait near Japan, China’s defense ministry said Monday, after Tokyo announced it may patrol with the US in the contested South China Sea region.
China’s Air Force on Sunday sent 40 planes over the Miyako Strait, between Japan’s Miyako and Okinawa Islands, to carry out training in the West Pacific, according to a statement on the defense ministry’s website.
The planes — Sukhoi Su-30 fighters, bombers and refueling aircraft — made the flights without violating Japan’s airspace.
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The drill is aimed at “testing far sea combat capabilities”, the statement said, and follows China’s first military flight over the Miyako Strait last year.
The move comes after Japanese defense minister Tomomi Inada said earlier this month that Tokyo would increase its engagement in the South China Sea through joint training cruises with the US Navy, exercises with regional navies and capacity-building assistance to coastal nations.
Beijing asserts sovereignty over almost all of the strategically vital waters, dismissing rival claims from its Southeast Asian neighbors.
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In recent months, Japanese Prime Minister Shinzo Abe has criticized China for rejecting a July ruling by an international tribunal that said Beijing’s extensive claims to the waters had no legal basis.
Tokyo, a key US ally, is also boosting defense ties with other countries in the disputed region, with the two Asian powerhouses already at loggerheads over a longstanding territorial row in the East China Sea.
That dispute relates to uninhabited islets controlled by Japan in the East China Sea, known as the Senkakus in Japanese and the Diaoyus in Chinese.
The Chinese defense ministry said in the statement that it had also mobilized an unspecified number of bombers and fighters to patrol in the East China Sea air defense identification zone (ADIZ).
Beijing sparked alarm after it unilaterally established the ADIZ in 2013, demanding all aircraft submit flight plans when traversing the zone, which covers islands disputed with Tokyo and also claimed by Taipei.
“Normalizing far sea drills out in the West Pacific and patrols in the East China Sea ADIZ is based on the need for China’s Air Force to protect national sovereignty and security and ensure peaceful development,” Air Force spokesperson Shen Jinke said in the statement.
The Chinese military has been monitoring and identifying foreign army planes that entered the ADIZ and “took measures according to different air threats” since the zone was set up three years ago, the statement added. CBB/rga