File photo shows a Su-35 fighter jet taking off. China has recently sent Su-35 fighter jets for a joint combat patrol mission in the South China Sea area, according to the People's Liberation Army (PLA) air force on Feb. 7, 2018. (Xinhua)
An undated file photo shows a J-20 stealth fighter. China's latest J-20 stealth fighters have been commissioned into air force combat service, a spokesperson confirmed Friday. (Xinhua)
