On the morning of September 11, 2001, Lieutenant Colonel Paul “Ted” Anderson noticed that his colleagues at the Pentagon were gathered around a TV. When he walked over, he learned that a plane had just crashed into the World Trade Center’s North Tower in New York City.

“I watched with them in amazement as the second airplane actually hit the second tower [at 9:03 A.M.],” says Anderson, who was then working for the secretary of the Army’s office of congressional and legislative affairs. “We watched it live, and I almost threw up.”

Soon after, Anderson received a call from his wife at the time, a sixth grade teacher in North Carolina, who was already watching and discussing the attacks with her class. He was on the phone with her and her class when a third plane, American Airlines Flight 77, struck the Pentagon between Wedges 1 and 2. Anderson was in Wedge 2.

“The entire building literally felt like it had completely lifted off the foundation,” he says. “I said, ‘We’ve been bombed, I have to go,’ and I hung up. And I got up and I started screaming for people to get out of the office.”

The attack on the Department of Defense headquarters in Arlington, Virginia killed 189 people in the building and on the plane (including the hijackers), and may have killed more if not for the actions of civilians, service members and first responders that day.

When the plane hit the Pentagon at 9:37 A.M., it wasn’t immediately clear to those in the building what had happened. As Anderson mentions, his first thought was that it was a bomb. One security guard warned Anderson to be careful opening the exit doors, fearing the bomb was a way to scare people out of the building so shooters could gun them down.

Anderson didn’t hear shooting outside, so he opened the doors, told people to get out and helped escort a pregnant worker to safety. Once outside, he and Army Staff Sergeant Christopher Braman—then working as a cook in the Pentagon’s general officer mess—ran toward the site where the plane had crashed.

“Chris and I noticed at that point that there were two women laying outside on the ground,” Anderson says. “The first woman that I came to had a compound fracture of the hip, and you could see the bone exposed. And at that point she was going into shock.”

Anderson carried the woman away from the building. Then, he and Braman ran back inside the Pentagon to look for others. They found a woman pinned beneath a nine-drawer safe (like a file cabinet, but heavier because each drawer is a safe), got her out from under it and helped her outside. They also found a man who was on fire, and worked to extinguish him and carry him outside.

The burned man told them there were others still stuck inside, so Anderson and Braman once again headed back to the building. They weren’t the only ones; other Pentagon workers were trying to get inside to save their colleagues too.

“And that’s when the confrontation with the fire department happened,” Anderson says.

Firefighters are trained to prevent people from going back inside a burning building once they’ve escaped, and they told the military members trying to return to the Pentagon that they had to stay outside. The conflict became heated, and some general officers had to step in to de-escalate.

“Everybody outside was incredulous,” Anderson says. “We know we have fellow soldiers, fellow sailors in there that are burning up and…we pledge to never leave a fallen comrade behind.” But he says he understands the firefighters’ position.

“It wasn’t [long] thereafter that that whole portion of the Pentagon caved in,” he says. “Had we been in there, we would’ve all been killed.”

Three-year-old Hanna Born and her baby sister Heather were at the Pentagon’s daycare center on 9/11, while their father worked in Alexandria and their mother, Lieutenant Colonel Dana H. Born (now a retired Air Force brigadier general), worked across the Potomac River at Bolling Air Force Base in Washington, D.C. Because their parents couldn’t immediately get to them, the sisters depended on the adults present that day to evacuate the daycare and keep them safe.

“I’m so grateful that even in the midst of such a tragic and horrifying event they came and took us to safety,” Hanna said in a 9/11 commemoration speech she delivered in 2019 as an Air Force Academy cadet. “I continue to be inspired by their resiliency and professionalism and so many others that day who asked to go back into the Pentagon to help others.”

Another person at the Pentagon that day was Lieutenant Colonel Patricia Horoho, an Army nurse. With nothing more than a simple first-aid kit, she set up a triage area outside of the building to care for dozens of injured people. (Horoho went on to become the Army’s first female surgeon general.)

Though the majority of the roughly 22,000 people at the Pentagon that day survived the attack, many sustained injuries leading to chronic health problems and suffered profound mental trauma. Braman developed a type of asthma from breathing in smoke, asbestos and jet fuel while rescuing others. His rescue work also exacerbated existing problems with his spinal discs, necessitating surgery.

Lieutenant colonel Marilyn Wills, then the Army's deputy chief of staff for personnel, suffered injuries while crawling out of the burning building. When one woman behind her looked like she wasn’t going to make it, Wills hoisted her on her back and kept crawling. (Wills recounts the story on HISTORY Channel’s 9/11: The Pentagon.) Afterward, she lost consciousness and had to go to the hospital to receive treatment for burns and smoke inhalation.

Nearly 20 years after the attack, the Pentagon is rebuilt and continues to serve as the headquarters for the Department of Defense. A memorial now sits just outside of the building, honoring the 59 people on the plane (not counting the five hijackers) and 125 people in the Pentagon who died that day.