This story was originally published in 2016 and has been updated.
Tuesday is the 17th anniversary of the Sept. 11, 2001 terrorist attacks.
The coordinated plot began with the hijacking of four planes and ultimately ended with the deaths of nearly 3,000 people in New York, the Washington, D.C.-area and Pennsylvania.
Below, a detailed look back at the events of that day, including video and photos. A word of warning: Much of the content may be disturbing, as anyone who lived through the day or witnessed its events already knows:
The airplanes hijacked on 9/11 begin taking off at 7:59 a.m.
The first to depart is American Airlines Flight 11, a Boeing 767 that leaves Boston’s Logan International Airport for Los Angles with 92 people on board.
At 8:14 a.m., United Airlines Flight 175 — a Boeing 767 with 65 passengers on board — leaves Logan for Los Angeles.
American Airlines Flight 77 leaves Washington Dulles International Airport at 8:20 a.m. The plane, a Boeing 757 with 64 people on board, is headed for Los Angeles.
Finally, at 8:42 a.m., United Airlines Flight 93 departs from Newark International Airport. The Boeing 757, which carries 44 passengers, is bound for San Francisco.
The first crash occurs at 8:46 a.m. when Flight 11 slams into the north tower of New York’s World Trade Center.
According to the 9/11 Commission Report, two flight attendants contact American Airlines as the plane is being hijacked to provide details of the emergency. They report the use of Mace or a similar spray, several stabbings and a bomb threat.
The last known communication from the plane comes when flight attendant Madeline “Amy” Sweeney, on the phone with American Flight Services manager Michael Woodward, says, “Oh my God we are way too low.”
The second crash comes at 9:03 a.m., when Flight 175 flies into the south tower of the World Trade Center.
The last communication made with air traffic control comes at 8:42 a.m., but passengers provide details of the flight by contacting their families by phone.
President George W. Bush learns of the attacks at 9:05 a.m. while sitting in a second grade classroom at an elementary school in Sarasota, Fla. White House Chief of Staff Andrew Card informs him of the attacks, whispering into his ear during the students’ reading lesson.
Bush later shares his memories of that day with National Geographic. He explains that when he receives news of the first plane crash at 8:50 a.m. — just before entering the classroom — he believes it is “a light aircraft,” and his reaction is “man, the weather was bad or something extraordinary happened to the pilot.”
It isn’t until Card informs him of the second plane that Bush understands America is under attack.
In an address from Emma Booker Elementary School in Sarasota, Fla., Bush calls the attacks “a national tragedy” and “an apparent terrorist attack on our country.”
“I have spoken to the vice president, to the governor of New York, to the director of the FBI, and have ordered that the full resources of the federal government go to help the victims and their families, and to conduct a full-scale investigation to hunt down and to find those folks who committed this act,” Bush says.
“Terrorism against our nation will not stand.”
At 9:36 a.m., Secret Service agents evacuate Vice President Dick Cheney and his aides from his office to the Presidential Emergency Operations Center, a Cold War-era bunker beneath the White House.
Flight 77 crashes into Pentagon.
According to the 9/11 Commission Report, passenger Barbara Olson calls her husband Ted — the solicitor general of the United States — to inform him of the attacks. She reports that the flight has been taken over and that the aircraft is “flying low over houses.”
A few minutes later, air traffic controllers at Dulles International Airport observe a plane on their radar traveling at “a high rate of speed.” Officials from Ronald Reagan Washington National Airport warn the Secret Service of the aircraft shortly before Flight 77 hits the Pentagon.
Just minutes after Flight 77 crashes into the Pentagon, the White House and U.S. Capitol are evacuated.
After burning for 56 minutes, the south tower of the World Trade Center collapses at 9:59 a.m. The fall, which kills approximately 600 workers and first responders, lasts 10 seconds.
The fourth hijacked plane crashes at 10:03 in a field in Shanksville, Pa.
The 9/11 Commission Report reports that several passengers make calls from the plane and receive word of the other hijackings. Upon hearing the news that major cities were being targeted, the passengers decide to fight back:
Five calls described the intent of passengers and surviving crew members to revolt against the hijackers. According to one call, they voted on whether to rush the terrorists in an attempt to retake the plane. They decided, and acted.
At 9:57, the passenger assault began. Several passengers had terminated phone calls with loved ones in order to join the revolt. One of the callers ended her message as follows:”Everyone’s running up to first class. I’ve got to go. Bye.”
According to the 9/11 Memorial, the hijackers deliberately crash in a field to prevent passengers from retaking the airplane. The crash site in Shanksville is approximately 20 minutes flying time from Washington, D.C.
After burning for 102 minutes, the north tower of New York’s World Trade Center collapses, killing approximately 1,400 people.
New York City Mayor Rudy Giuliani orders an evacuation of lower Manhattan, alerting everyone south of Canal Street to leave.
After all American air space has been cleared, Bush addresses the nation from Barksdale Air Force Base in Louisiana, informing citizens that the U.S. military “at home and around the world is on high alert status.”
“Make no mistake, the United States will hunt down and punish those responsible for these cowardly acts,” Bush says.
Hours after the attacks that morning, the 47-story 7 World Trade Center building collapses from ancillary damage. No one is in the building at the time.
Bush gives his final address of the day from the White House.
From the Oval Office, the president informs Americans that he has implemented federal emergency response plans, noting emergency teams and the military are already at work:
Today, our fellow citizens, our way of life, our very freedom came under attack in a series of deliberate and deadly terrorist acts.
The victims were in airplanes or in their offices — secretaries, businessmen and women, military and federal workers. Moms and dads. Friends and neighbors.
Thousands of lives were suddenly ended by evil, despicable acts of terror.
The pictures of airplanes flying into buildings, fires burning, huge structures collapsing, have filled us with disbelief, terrible sadness and a quiet, unyielding anger.
These acts of mass murder were intended to frighten our nation into chaos and retreat. But they have failed. Our country is strong. A great people has been moved to defend a great nation.