Slahi lived in Montreal , Quebec , Canada from November 1999 to January 2000 , during which the millennium attack plots were thwarted . Slahi was suspected of involvement in the attempted LAX bombing and was investigated by the Canadian Security Intelligence Service . Due to the scrutiny , Slahi returned to live in Mauritania , where he was questioned and cleared of involvement . After the September 11 attacks , the U.S. again was interested in Slahi . He turned himself in to Mauritanian authorities for questioning about the millennium plot on November 20 , 2001 . He was detained for seven days and questioned by Mauritanian officers and by agents of the U.S. Federal Bureau of Investigation ( FBI )
September 11 attacks
September 11 attacks
Mohamedou Ould Slahi