Japanese fighter jet scrambles against Chinese planes hit a record high in the year that ended in March, the Defense Ministry said on Wednesday, as Sino-Japanese ties were strained by disputes over territory and interpretations of history.
Japan scrambled combat planes against Chinese aircraft 415 times during the year, up 36 percent from a year earlier. It was the highest number since the ministry started disclosing country-specific figures in 2001.
Relations have been plagued by China's memories of Japan's occupation of parts of China before and during World War Two and conflicting claims over a group of tiny East China Sea islets.
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Tensions mounted further after China in November declared an air defense identification zone covering a large swathe of the East China Sea, including the disputed isles, and Japanese Prime Minister Shinzo Abe's visit in December to Yasukuni Shrine, seen by critics as a symbol of Japan's wartime aggression.
"As for China, we understand they are keeping up vigorous activities," Akira Asai, public affairs director of the Defense Ministry's Joint Staff, told a briefing.
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Over the past year, Chinese fighter jets and other planes appear to have expanded their range of activities, Asai said.
In one such instance, a Chinese Y-8 airborne early warning plane flew for the first time through international airspace near Japan's southern islands over the Pacific last July and took the same route back over the East China Sea.
Scrambles against Russian planes rose 45 percent to 359 times during the year, also a record. As a result, Japan's total scrambles came to 810 to hit a 24-year high.