who did 911

The 9/11 attacks were carried out by 19 terrorists associated with the Islamist extremist group al-Qaeda, led by Osama bin Laden. These hijackers commandeered four American passenger airplanes on September 11, 2001, crashing two into the Twin Towers of the World Trade Center in New York City, a third into the Pentagon near Washington, D.C., and the fourth into a field in Pennsylvania after passengers attempted to take back control. The attacks killed nearly 3,000 people and were orchestrated as a response by al-Qaeda to U.S. involvement in the Muslim world. The key planner was Khalid Sheikh Mohammed, and the hijackers were mainly Saudi nationals. Following the attacks, the U.S. launched a war on terror including the invasion of Afghanistan to dismantle al-Qaeda and capture bin Laden.