Chinese aircraft approaches Japanese destroyer in E. China Seaï¼ æ¯Žæ—¥ï½Šï½(æ¯Žæ—¥æ–°èž) TOKYO (Kyodo) -- A Chinese fixed-wing aircraft on Thursday approached a Japanese destroyer that was patrolling near the median line that ostensibly separates the two countries' exclusive economic zones in the East China Sea, immediately triggering a protest from Tokyo. The plane, marked with the flag of China and Chinese characters indicating its affiliation with the State Oceanic Administration, at one point approached as near as 50 meters to the Japanese Maritime Self-Defense Force destroyer Asayuki at around 12:10 p.m. on Thursday in the area where the two countries' 200-nautical-mile EEZs overlap. The Japanese Foreign Ministry urged Beijing not to repeat such a flight, which it described as "a dangerous act." The Joint Staff Office of the Japanese Defense Ministry said the Chinese aircraft approached the MSDF destroyer in the Japanese EEZ near the Chunxiao gas field, known as Shirakaba in Japan. The two countries are at odds over gas development in the area. Beijing does not recognize the median line and claims its EEZ stretches further to the edge of the continental shelf, nearer Okinawa Prefecture. The Asayuki was mobilized for routine patrol activities and not for an emergency response in the event North Korea goes ahead with its planned rocket launch, which is widely suspected to be a covert test of a long-range ballistic missile, according to the office. Meanwhile, two Russian surveillance planes flew over the Sea of Japan and the East China Sea between 8 a.m. and 5 p.m. Thursday, prompting Japan's Air Self-Defense Force to scramble jets to guard against an airspace incursion. The Defense Ministry said the Tu-142 aircraft did not violate Japan's airspace but repeatedly flew around over the East China Sea north of Miyako Island in Okinawa Prefecture. The ministry suspects the Russian planes were collecting data on the Japanese and U.S. response to the planned rocket launch by North Korea, which involves the deployment of Aegis destroyers and ground-based radar by Japan and the United States.