Omar Abdel-Rahman
According to statements by Lt. Col. Anthony Shaffer and those of four others, Able Danger had identified 2 of 3 Al Qaeda cells active in the 9/11 attacks; the 'Brooklyn cell' linked to Blind Sheik Omar Abdel-Rahman, including September 11 attacks leader Mohamed Atta, and three of the 9/11 plot's other 19 hijackers, as possible members of an al Qaeda cell linked to the 1993 World Trade Center bombing.