Japan lodged a protest with China on Sunday after Chinese warplanes directed fire-control radar at Japanese fighter planes near Okinawa islands.
Japan’s Defense Minister Shinjiro Koizumi described the Chinese military’s moves as “dangerous.”
“These radar lights were in excess of the limits required for the safe flight of the aircraft,” he said.
“It is extremely regrettable that such an incident took place,” the minister said. “We have lodged a strong protest with the Chinese side and demanded strict preventive measures.”
Radar lock is considered one of the most dangerous acts by military aircraft as it signals a possible attack, forcing the target aircraft to take evasive action.
Fighter aircraft can also use radar for search.
What do we know about the incident?
Japan’s Defense Ministry said Chinese J-15 military jets “intermittently” aimed their radar at Japanese F-15s in two incidents on Saturday – for about three minutes in the afternoon and for 30 minutes in the evening.
It was not immediately known whether the radar lock on both occasions was of the same Chinese J-15.
Japan said the Chinese J-15 aircraft involved in the two radar lock incidents were launched from China’s Liaoning aircraft carrier.
The Liaoning was maneuvering between the main island of Okinawa and nearby Miyako Island on Saturday as it practiced aircraft takeoff and landing in the Pacific.
The ministry said the radar lock was detected by various Japanese fighter aircraft, which were scrambling against possible airspace violations by China.
Japanese airspace was not violated.
“China’s intentions are unclear, but if it wants to locate (the plane), there is no need to do so intermittently,” Japan’s Kyodo news agency quoted a defense ministry official as saying at a news conference.
Japan’s statement on Sunday marked the first time that the Defense Ministry in Tokyo publicly disclosed the fire-control radar lock incident by Chinese military jets against Japanese aircraft, according to Japanese media.
In 2013, Japan said a Chinese warship locked its radar onto a Japanese destroyer in the East China Sea.
China-Japan relations deteriorated over Taiwan
The radar-lock incident is the latest dispute between the two Asian countries, whose relations have soured in recent weeks over Taiwan, the self-ruled island that China claims as its territory.
Japanese Prime Minister Sanae Takaichi said in November that his country’s military could get involved if China took action against Taiwan, irking Beijing.
Edited by: Dmytro Lyubenko