Raissi was born and grew up in Bab el Oued, a suburb of Algiers. In November 1996 he moved to Phoenix, Arizona, USA to attend flight school, including a 1998 stint at Sawyer School of Aviation a month after Hani Hanjour quit. In April 2000, when his student visa expired, he moved back to Algeria and then to London, with his wife Sonia (née Demolis), whom he had met in the United States. From June 11-18, 2001, Raissi had apparently visited Las Vegas, while Ziad Jarrah was in the city.
Raissi was living outside Colnbrook (near Heathrow) at the time of the attacks. He was arrested at 3 am on September 21, 2001, when he was taken from his house naked, along with his wife Sonia and his brother. The Times obtained a copy of the FBI's initial request for information about Raissi. In it, The Times asserts, the FBI requested that British authorities use discretion, in order not to tip him off that he was under suspicion.
Raissi's brother and wife Sonia were released by British police four days after the arrests, although Sonia lost her job working with Air France and his brother's wife lost her job at Heathrow Airport as well. From there Raissi was detained for five months at Belmarsh Prison, under suspicion of training the pilots who flew the jet into the Pentagon. He was also charged with using a "false identity" having gone by the name "Fabrice Vincent Algier", and for conspiring to help Redouane Dahmani lie on his visa application.