There were 2,974 victims and 19 hijackers were killed on September 11, 2001. Also, it was proven that one person died from lung damage due to smoke inhalation after the attacks. A number of planned suicide attacks on the U.S. were carried out by Al-Qaeda. Four commercial airplanes were hijacked by terrorists. Two of the planes crashed into the Twin Towers of the World Trade Center, and both buidlings collapsed. A third plane crashed into the Pentagon in Virginia, and the fourth plane crahed in a rural part of Pennsylvania.