Photo taken on Aug. 15, 2019 shows travellers at Hong Kong International Airport in Hong Kong, south China. The operation of Hong Kong International Airport returned to normal on Thursday, the Airport Authority Hong Kong said. The airport's operation had been seriously affected over the past few days by unlawful assemblies, with 979 flights being canceled, chief executive officer of the airport authority Fred Lam told a press conference on Wednesday. (Xinhua/Lui Siu Wai)