Two armed policemen guard at terminal 3 of the Beijing Capital International Airport in Beijing, China, on July 20, 2008. The Beijing Capital International Airport has implemented special security checks to ensure air transport safety during the upcoming Olympics since July 20. The security checking equipments are installed at the entrances of all three terminal buildings of the airport, and passengers, people who come to receive or see the passengers off as well as those who work at the airport would all have to undergo security checks if they are to enter the airport. (Xinhua Photo)