It has been 15 years since the September 11 attacks, when four passenger planes, operated by two major US air carriers were hijacked by 19 members of al-Quaeda, killing 2,996 people and injuring more than 6,000.
Two of the planes, American Airlines, Flight 11 and United Airlines, Flight 175, were deliberately crashed into the upper floors of the North and South towers of the World Trade Center (WTC). Flight 11 hit floors 93 to 99 of the North Tower (1 WTC) at 8.46 m local time and Flight 175 struck floors 77 to 85 of the South Tower (2 WTC) 17 minutes later at 9.03 am. In under two hours, both 110-storey towers had collapsed. Between 16,400 and 18,000 people were in the WTC complex when the towers were struck. Of those, the vast majority evacuated safely, but many did not.
A third plane crashed into the Pentagon, the headquarters of the United States Department of Defense in Arlington, Virginia, leading to a partial collapse of the buildings western side. After learning about the other attacks, passengers on the fourth hijacked plane, Flight 93, intercepted the hijackers and the plane was crashed into an empty field in western Pennsylvania about 20 minutes by air from Washington, DC.
Smoke rises from the southwest E-ring of the PentagonAlex Wong/ Getty ImagesThe Washington Momument stands in the background as the Pentagon burns after a hijacked plane crashed into the buildingGreg Whitesell/ Getty ImagesRecue workers and Pentagon personnel attend to the wounded outisde the PentagonGreg Whitesell/ Getty ImagesFirefighters struggle to contain spreading fire after the highjacked commercial jetliner crashed into the Pentagon in Arlington, VirginiaTSgt Jim Varhegyi/ Getty Images
The 9/11 attacks are a powerful memory for Americans, and for the world. According to poll conducted by Pew Research Center, 91% of the adults that were surveyed remember exactly where they were or what they were doing when they heard news. Thousands of volunteers went to Ground Zero to help with the rescue, recovery and clean-up efforts. "We will rebuild. We're going to come out of this stronger than before, politically stronger, economically stronger. The skyline will be made whole again." Rudy Giuliani, mayor of New York City on the day of the fatal events.
Spectators look up as the World Trade Center goes up in flamesSpencer Platt/ Getty ImagesPeople walk in the street in the area where the World Trade Center buildings collapsedMario Tama/ Getty ImagesA New York City ambulance burns in the street near the World Trade CenterShannon Stapleton/ ReutersPeople take cover as a dust cloud from the collapse of the World Trade CenterMario Tama/ Getty ImagesDust and debris fill the air as one of the World Trade Center towers collapsesJose Jimenez/ Primera Hora/ Getty ImagesMarcy Borders covered in dust as she takes refuge in an office building after one of the World Trade Center towers collapsedStan Honda/ AFPA man walks in the street after the collapse of the World Trade CenterShannon Stapleton/ ReutersRescue workers remove an injured man from the World Trade Center TowerShannon Stapleton/ ReutersA man, who survived the attack, sits outside the World Trade CenterJose Jimenez/ Primera Hora/ Getty ImagesA man shouts for a friend following the attack on the World Trade CenterEzra Shaw/ Getty ImagesPeople evacuate the area around the World Trade CenterMario Tama/ Getty ImagesPeople walk away from the World Trade Center towersShannon Stapleton/ Reuters
US President George W Bush was informed of the attacks by House Chief of Staff Andrew Card while conducting a reading seminar at the Emma E Booker Elementary School in Florida. Bush continued the reading lesson, before returning to Washington. Writing in his book, Decision Points, Bush describes the contrast between what was happening in New York City and the innocent children sitting in front of him. "I looked at the faces of the children in front of me. I thought about the contrast between the brutality of the attacks and the innocence of those children. Millions like them would soon be counting on me to protect them. I was determined not to let them down." Bush returned to Washington after the reading, where he was joined by his aides.
White House Chief of Staff Andrew Card, left, informing US President George W. Bush of the attacks on the World Trade CenterPaul J Richards/ AFPUS President George W Bush speaks to his staff inside the private dinning room at The White House prior to his address to the nation about the terrorist attacksPaul Morse/ Getty ImagesUS Vice-President Dick Cheney and senior staff meet in the President's Emergency Operations Center (PEOC) after the terrorist attacks in WashingtonDavid Bohrer/ Getty ImagesUS Vice-President Dick Cheney in the President's Emergency Operations Center (PEOC) after the terrorist attacks in WashingtonDavid Bohrer/ Getty ImagesNational Security Advisor Condoleezza Rice in the President's Emergency Operations Center (PEOC) after the terrorist attacks in WashingtonDavid Bohrer/ Getty Images
Tons of wreckage – twisted steel beams weighing up to 40,000 pounds, chunks of concrete smelling of smoke, a crushed fire engine, a dust-covered airline slipper – were salvaged from the World Trade Center site for preservation in the weeks after the attacks. The New York City Fire Department deployed 200 units (half of the department) to the World Trade Center. The New York City Police Department sent emergency service units and other police personnel, and deployed its aviation unit. Police and rescue workers from around the country took leaves of absence, travelling to New York City to help recover bodies from the remnants of the Twin Towers. Blood donations across the US surged in the weeks that followed. 9/11 was the deadliest incident for firefighters and law enforcement officers in US history, and remains the worst attacks on US soil since Pearl Harbor.
A law enforcement officer reacts after the first tower of the World Trade Center fell in New York CityShannon Stapleton/ ReutersVolunteers donate blood at Lutheran General Hospital in Park Ridge, Illinois, at a blood donation station set up to help victims of the World Trade Center on the day of the attacksTim Boyle/ Getty ImagesA fireman runs as the World Trade Center collapses after two planes hit the buildingJose Jimenez/ Primera Hora/ Getty ImagesA New York city firefighter carries a waterhose on Vessey and Greenwich Streets in lower Manhattan after the World Trade Center is hitReutersNew York City firefighters hug each other during rescue operations at the World Trade CenterRon Agam/ Getty ImagesNew York firefighter John Cleary wipes the soot from his face while taking a break from rescue work at the World Trade CenterBrad Rickerby/ ReutersFirefighters make their way through the rubble of the World Trade Center following the attackDoug Kanter/ AFPA man stands among the debris in the rubble, as he calls out asking if anyone needs help, following the collapse of the first World Trade Center TowerDoug Kanter/ AFP
Commemoration ceremonies will be held around the world on Sunday to mark the 15th anniversary of the attacks. This will include an NYPD parade and Tribute in Light, an art installation placed next to the site next to the World Trade Centre, which creates two vertical columns of light. An exhibition entitled "Rendering the Unthinkable: Artists Respond to 9/11." is also showing at the 9/11 Memorial & Museum.
12 September, 2001: Photographs of missing people from the World Trade Center attack are placed on a television truck outside the Bellevue HospitalJohn Mottern/ AFP13 September, 2001: US President George W. Bush's eyes well up with tears while speaking in the Oval Office of the White HouseKevin Lamarque/ Reuters14 September, 2001: Rescue workers conduct search and rescue attempts, descending deep into the rubble of the World Trade CenterJim Watson/ Getty Images15 September, 2001: Firefighters attend a funeral service for New York Fire Department Chaplain Rev. Mychal Judge, in front of the St. Francis of Assisi ChurchJoe Raedle/ Getty Images15 September 2001: A firefighter wipes a tear while saluting the casket of New York Fire Department Chaplin Reverend Mychal Judge, a victim of the World Trade Center attackStan Honda/ AFP15 September, 2001: Smoke rises from the site of the World Trade Center terrorist attackNYC Office Of Emergency Management/ Getty Images15 September, 2001: A rescue dog is transported out of the debris of the World Trade CenterJim Watson/ Getty Images17 September, 2001: Pedestrians pause at a memorial in Times Square for victims of the World Trade Center attack in New YorkEric Feferberg/ AFP19 September, 2001: New York resident Janine Llyette cries at seeing the remains of the World Trade Center for the first timeRoberto Schmidt/ AFP24 September, 2001: Rescue workers search through the wreckage of the World Trade CenterTed Warren/ AFP25 September, 2001: View from the top of the escalators in the Bankers Trust building show the wreckage of the World Trade Center25 September, 2001: View through a broken out office window shows the wreckage of the World Trade CenterEric Feferberg/ AFP