Nov. 30 (UPI) -- China's defense ministry suggested Friday South Korea should not raise the issue of Chinese military aircraft trespassing in Korea's Air Defense Identification Zone.
Chinese defense ministry spokesman Ren Quoqiang told reporters Friday at a regular press briefing South Korea's KADIZ is not sovereign airspace, although the zone was established in 1951 during the Korean War.
Seoul filed an official complaint with Beijing's ambassador to South Korea after a Chinese military aircraft, possibly a Y-9 reconnaissance plane, entered the KADIZ on Monday -- the seventh time this year the Chinese trespassed South Korea airspace without notification, South Korean newspaper Donga Ilbo reported.
The Korean government requires all aircraft to send flight plans an hour prior to departure, if the flight route involves flying into South Korea airspace.
On Friday, Ren suggested the South Koreans were creating uproar over a legitimate exercise, Korean news service Newsis reported.
"The exercise in question is part of an annual training of the Chinese air force, and conforms to international laws and customs," the Chinese spokesman said. "We hope the South Korean side will not be startled by such an insignificant event."
China deployed a spy plane on Monday to collect intelligence on South Korea terrain and activity, South Korean military authorities said this week.
Seoul scrambled F-15K fighter jets on the day of the intrusion, sending warning messages to the Chinese aircraft.
The spy plane consistently ignored the messages for two hours and continued on its route in the KADIZ before leaving the area, according to reports.