Premise: The September 11 , 2001 , attacks in the northeast United States were an organized terrorist act carried out by 19 hijackers , and organized by numerous members of al-Qaeda . September 11 attacks . were a series of four coordinated terrorist attacks by the Islamic terrorist group al-Qaeda on the United States on the morning of Tuesday , September 11 , 2001 . Four passenger airliners operated by two major U.S. passenger air carriers ( United Airlines and American Airlines ) -- all of which departed from airports in the northeastern United States bound for California -- were hijacked by 19 al-Qaeda terrorists . Although al-Qaeda 's leader , Osama bin Laden , initially denied any involvement , in 2004 he claimed responsibility for the attacks .
Hypothesis: The September 11 attacks were carried out by members of al-Qaeda.
Label: ENTAILMENT