A total of 2,996 people were killed in the 9/11 attacks, including the 19 terrorist hijackers aboard the four airplanes.
On September 11, 2001, 19 militants associated with the Islamic extremist group al-Qaeda hijacked four airplanes and carried out suicide attacks against targets in the United States. Two of the planes were flown into the twin towers of the World Trade Center in New York City, a third plane hit the Pentagon just outside Washington, D.C., and the fourth plane crashed in a field in Pennsylvania.
Almost 3,000 people were killed during the 9/11 terrorist attacks, which triggered major U.S. initiatives to combat terrorism and defined the presidency of George W. Bush.
At the World Trade Center, 2,763 died after the two planes slammed into the twin towers. That figure includes 343 firefighters and paramedics, 23 New York City police officers and 37 Port Authority police officers who were struggling to complete an evacuation of the buildings and save the office workers trapped on higher floors.
At the Pentagon, 189 people were killed, including 64 on American Airlines Flight 77, the airliner that struck the building. On Flight 93, 44 people died when the plane crash-landed in Pennsylvania.
Find more facts about the 9/11 attack at History.com.