South Korea summoned the Chinese ambassador on Tuesday to lodge a complaint over a Chinese military aircraft entering the South's air defense identification zone (KADIZ), the second such incident this year, the Foreign Ministry said Wednesday.
The Chinese aircraft flew for more than four hours inside South Korea's KADIZ on Tuesday, prompting the South to scramble multiple fighter jets to track it, a South Korean defense official said.
The ministry said Ambassador Qiu Guohong was told the military jet's flight into South Korean airspace had been "unfortunate" and was urged to prevent similar instances from occurring again.
The Chinese aircraft on Tuesday also entered Japan's ADIZ, prompting Tokyo to scramble fighter jets.
Three other Chinese officials based in South Korea had been summoned to the Defense Ministry earlier in the day over the incident, which occurred near the island of Ulleungdo off the east coast.
The aircraft was told to "halt its threatening flight" and "any other actions that could raise the possibility of sudden conflict," said the South Korean defense official, adding that Chinese officials had told South Korea's military that the aircraft's movements had been part of regular military exercises.
China's Foreign Ministry did not immediately respond to a request for comment.
A Chinese military aircraft entered the KADIZ on Jan. 29, and two similar instances were observed in 2017.