President Donald Trump posthumously awarded the Presidential Medal of Freedom on Tuesday to Welles Remy Crowther, recognizing his heroic efforts in rescuing 18 people from the south tower of the World Trade Center during the attacks on September 11, 2001. Crowther, an equities trader at the time, died when the building collapsed.

The ceremony took place on the Ellipse, a park just south of the White House, and also honored the emergency workers who responded to the attacks. Trump praised Crowther’s repeated acts of bravery, describing how he moved “up and down, up and down, over and over again, saving life after life.”

Crowther was 24 years old and working on the 104th floor of the south tower when United Airlines Flight 175 struck. His rescue efforts primarily took place on the 78th floor and were later recounted by survivors who referred to their savior as “the man in the red bandanna.” Crowther had used a red bandanna, given to him by his father, to protect himself from smoke and fire during his efforts to help others evacuate.

In 2002, Crowther’s identity became widely known after his mother, Alison Crowther, recognized him from a New York Times article featuring survivors’ accounts. She said her son’s prior experience as a volunteer firefighter with Empire Hook and Ladder Company No. 1 in Nyack, New York, was instrumental in enabling him to act with such effectiveness that day. “He was no longer an equities trader on 9/11; he was a firefighter,” she said during the ceremony. Several members of the same volunteer firefighting company attended the event.

Crowther’s actions involved guiding those who could walk to the remaining functional stairwell and physically carrying others down to safety. President Trump noted that Crowther was in the lobby of the south tower when it collapsed, leading to his death.

The decision to award Crowther the nation’s highest civilian honor was announced by Trump in May. The move was supported by Representative Mike Lawler, a Republican from New York, who had campaigned for Crowther’s recognition and introduced legislation for a Congressional Gold Medal in his honor. Trump said the medal was promised to Crowther’s family years ago and emphasized, “We didn’t forget. We never forget.”