On September 11, 2001, the 9/11 attacks took place in the United States, causing widespread devastation and loss of life. Coordinated by the terrorist group al-Qaeda, four commercial airliners were hijacked by terrorists. Two planes were flown into the Twin Towers of the World Trade Center in New York City, causing both towers to collapse. A third plane struck the Pentagon in Arlington, Virginia, while the fourth, United Airlines Flight 93, crashed into a field in Pennsylvania after passengers fought the hijackers. The attacks resulted in nearly 3,000 deaths and significant changes to U.S. domestic and foreign policy, including the initiation of the War on Terror.