TOKYO, Feb. 21 (UPI) -- China has rapidly increased its aerial surveillance within Japan's air-defense zones this year, the Sankei Shimbun reported Tuesday.
In last year's official report on its maritime activities, China admitted mobilizing surveillance planes 146 times over disputed areas of the East China Sea, the newspaper said.
According to Japan's Defense Agency, the number of flights scrambled to intercept invading Chinese planes increased from zero in 2002 to 30 incidents in recent months.
Chinese reconnaissance aircraft, mainly flying over gas fields in the East China Sea, are apparently engaged in gathering electronic information such as radar frequencies emitted by Japan's Air Self-Defense jets or from ground bases, the newspaper added.
