During the president's video teleconference with key administration officials, Director of Central Intelligence George Tenet reports that evidence points to the al Qaeda organization as the mastermind behind
the attacks.1

1 Goldberg, A. Papadopoulous, S., et al “Pentagon 9/11” Historical Office, Office of the Secretary of Defense n.d PDF. March 17, 2011 page 130 http://osdhistory.defense.gov/docs/Pentagon%209-11.pdf