Prior to the attacks of Sept. 11, hijackers criss-crossed around the country, making what the FBI suggests to be pre-attack surveillance trips.
These cross-country flights began about three months prior to the attacks. The hijackers traveled from New York, metropolitan Washington, Boston, San Francisco and Los Angeles.
Investigators say the hijackers all booked return flights with layovers in Las Vegas, but that the reason behind these layovers is yet unknown.
The identity of a Middle Eastern man who accompanied hijacker Marwan al-Shehhi in late August 2001 to the Miami airport, where al-Shehhi bought his ticket for the plane he flew into the second World Trade Center, is also unknown.
Another mystery is why Muhammed Atta took a trip to Portland, Maine, the night before the attacks, or why in January 2001 he left the country to visit Madrid, Spain. At this same time, al-Shehhi is reported to have visited Casablanca, Morocco.
Investigators recently revealed that they now know for sure that Khalid al-Midhar was central to the terrorists’ plans. He is believed to be the man who recruited the hijackers. It was also revealed that all the hijackers did not sit in first class, as was earlier suspected. The pilot was in first class, while two were in business class and one man was traveling in coach.
The FBI said the Sept. 11 plot cost about $500,000 and that the presumed pilot of United Flight 175, Al-Shehhi, appears to have been in charge of the financing.
The financing effort is believed to have started in July 1999, two years prior to the attacks, when Al-Shehhi opened a bank account in the United Arab Emirates. Much of the money was then transferred to Atta. According to the FBI, other money was received from a man identified as Ali Abdul Aziz Ali, who has used many aliases.