Hong Kong Airport Security Unit conducts a drill in front of an audience on the open day celebrating the unit's 40th anniversary, on Saturday, September 9, 2017.(Photo: China News Service/Tan Daming)
Hong Kong Airport Security Unit conducts a drill in front of an audience on the open day celebrating the unit's 40th anniversary, on Saturday, September 9, 2017.(Photo: China News Service/Tan Daming)