2001 – The September 11 attacks, a series of coordinated terrorist attacks killing 2,977 people using four aircraft hijacked by 19 members of al-Qaeda. Two aircraft crash into the World Trade Center in New York City, a third crashes into The Pentagon in Arlington County, Virginia, and a fourth into a field near Shanksville, Pennsylvania. The September 11 attacks, commonly known as 9/11, were four coordinated Islamist terrorist suicide attacks carried out by al-Qaeda against the United States in 2001. On that morning, 19 terrorists hijacked four commercial airliners scheduled to travel from the East Coast to California. The hijackers crashed the first two planes into the Twin Towers of the World Trade Center in New York City and aimed the next two flights toward targets in or near Washington, D.C., in an attack on the nation's capital. The third team succeeded in striking the Pentagon, the headquarters of the U.S. Department of Defense in Arlington County, Virginia, while the fourth plane crashed in rural Pennsylvania during a passenger revolt. The September 11 attacks killed 2,977 people, making it the deadliest terrorist attack in history. In response to the attacks, the United States waged the multi-decade global war on terror to eliminate hostile groups deemed terrorist organizations, as well as the foreign governments purported to support them, in Afghanistan, Iraq, Syria, and several other countries. The Central Intelligence Agency informed President George W. Bush that its Counterterrorism Center had identified the attacks as having been the work of Al-Qaeda under Osama bin Laden. The United States formally responded by launching the war on terror and invading Afghanistan to depose the Taliban, which rejected the conditions of U.S. terms to expel Al-Qaeda from Afghanistan and extradite its leaders. The U.S.'s invocation of Article 5 of the North Atlantic Treaty—its only usage to date—called upon allies to fight Al-Qaeda. As U.S. and NATO invasion forces swept through Afghanistan, bin Laden eluded them by disappearing into the White Mountains. He denied any involvement until 2004, when excerpts of a taped statement in which he accepted responsibility for the attacks were released. Al-Qaeda's cited motivations included U.S. support of Israel, the presence of U.S. military bases in Saudi Arabia and sanctions against Iraq. The nearly decade-long manhunt for bin Laden concluded on May 2, 2011, when he was killed during a U.S. military raid on his compound in Abbottabad, Pakistan.