Air Force spokesman Shen Jinke said that on Friday morning, Chinese pilots had identified two US surveillance aircrafts and 10 Japanese planes – including early warning aircraft, surveillance aircraft and fighter jets – crossing through the ADIZ, state media reports.

He made no reference whether any further action was taken by any of the aircraft.

Earlier army spokesman Qin Gang said China had a right to patrol the region and that freedom of flight over the East China Sea was unaffected.