There were a total of 19 hijackers involved in the September 11, 2001 terrorist attacks. These 19 Al Qaeda terrorists hijacked four commercial passenger planes in the United States
. The distribution of hijackers on the planes was as follows:
- American Airlines Flight 11: 5 hijackers
- United Airlines Flight 175: 5 hijackers
- American Airlines Flight 77: 5 hijackers
- United Airlines Flight 93: 4 hijackers
This sums up to a total of 19 hijackers across the four flights
