They added that the aircraft had left the area five minutes later, and the patrol had sent a helicopter to warn and expel the aircraft.
Wu Jianghao, the Chinese ambassador to Japan, also lodged a stern protest over the “illegal intrusion”, saying the move severely violated China’s sovereignty and asked the Japanese side to take measures to avoid a repetition.
“China strongly deplores and resolutely opposes such an incident. If Japan takes any new provocative moves, China will resolutely take countermeasures to defend our sovereignty and maritime rights,” Wu said, according to the Chinese embassy.
Meanwhile Japan lodged its own protest with Beijing, saying four Chinese coastguard ships had been spotted in its “territorial waters” around the islands.
