The 19 hijackers involved in the September 11, 2001 attacks were affiliated with the jihadist organization al-Qaeda and came from four countries. Their nationalities were:
- 15 were citizens of Saudi Arabia
- 2 were from the United Arab Emirates
- 1 was from Egypt
- 1 was from Lebanon
These men were organized into four teams, each led by a pilot-trained hijacker, and carried out the attacks by hijacking four commercial airplanes
