F93VC_160530_220
Existing comment: Late 2000: At al Qaeda training camps in Afghanistan, hijackers undergo training in how to disarm air marshals, handle explosives, use knives, and storm an airplane's cockpit.

December 2000: Another al Qaeda-trained terrorist -- already possessing a commercial pilot's license -- arrives in the United States and enrolls in pilot and jet-simulator training in Arizona.

April 2001: More al Qaeda-sponsored terrorists begin arriving in the United States to fill out the four terrorist teams. The 19 terrorists who take part in the September 11 attacks are from Saudi Arabia, the United Arab Emirates, Lebanon, and Egypt.

May-September 2001: The hijackers prepare for their operation by taking additional flight training, fitness training, purchasing knives, and testing domestic security practices by boarding commercial flights with concealed weapons. Hijacker-pilots take cross-country surveillance flights.

July 2001: The leader of the hijacker teams meets with another al Qaeda operative in Spain to discuss the final plans and potential targets for the September 11 attacks.

August 4, 2001: Jose Melendez-Perez, a US Customs and Border Patrol agent, refuses to allow a Saudi citizen into the United States at Orlando International Airport in Florida. The man turned away may have been a fifth hijacker who planned to board Flight 93.
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