The World Trade Center’s South Tower collapsed at 9:59 a.m. after burning for nearly 100 minutes.
And North Tower collapsed at around 10:28 a.m. after burning for more than 100 minutes, according to The National Commission on Terrorist Attacks Upon the United States.
Later in the day, the 7 World Trade Center collapsed at 5:21 p.m. due to fires that were caused when the North Tower collapsed.
The total death toll was 2,752, including 157 passengers on board the two airplanes that collided into the buildings.
On Wednesday, there were memorial services across New York City and the United States to mark the day.
President Barack Obama also paid tribute.
“Our hearts still ache for the futures snatched away, the lives that might have been.” Obama said, according to USA Today.
He added: “We pray for all those who have stepped forward in those years of war -- diplomats who serve in dangerous posts, as we saw this day last year in Benghazi, intelligence professionals, often unseen and unheralded who protect us in every way; our men and women in uniform who defend this country that we love.”
