Twenty years ago, on September 11, our country changed forever and at the center of the devastation was my father: Officer F. Cortez.

On Sept. 11, 2001, a terrorist group named Al-Qaeda hijacked four airplanes and carried out multiple attacks against the United States. Two of the planes were flown into the World Trade Center in New York City, with a third plane hitting right outside of Washington, D.C. The fourth plane crashed into a field in Shanksville, Pennsylvania, but was believed to be intended for the White House.

My father, Officer Cortez, was a police officer in the NYPD at the time. Officer Cortez was testifying in court on 9/11 in Brooklyn when he saw a plane hit the north tower through the courthouse window. He immediately knew this was an attack and made the decision to head towards the burning tower to help. During the attacks, the subway and other transportation came to a halt, but that did not prevent him from reaching the tower.

“I ran across the Brooklyn Bridge to the WTC [World Trade Center] to help people come out of the buildings when the second plane hit,” Officer Cortez recounts. “I helped as many people as I could.”

Once the second plane hit, my father ran into a store nearby to take cover just before the windows shattered from the force of the building collapse. He remembers hearing a female officer who was inside the building asking for help over his radio.

“After both buildings fell, myself and thousands of other people walked across the Brooklyn Bridge, I just remember how quiet it was,” Officer Cortez stated. “I walked from Manhattan all the way to Brooklyn, covered head-to-toe in dust.”

After the attack, Cortez’s shifts as an officer consisted of him going to ground zero to assist with the cleanup. Even after his shift was over, he would go back to help look for survivors and clean up debris.

Cleanup at ground zero officially ended May 30, 2002, after nine months of work. Officer Cortez would sometimes bring his camera with him during his shifts to document the various states of rubble.

“I decided to bring my camera with me because this was something that had never happened before,” Cortez explained. “It felt like a war zone, and wars need to be documented.”

Sept. 11, 2001, will go down in history not only as one of the most horrific and saddening days the U.S. has seen, but as the day our country united together to help one another and show that everyday people like my father can become heroes.

“It feels like it happened yesterday, it doesn’t feel like much time has passed let alone 20 years,” Cortez explained. “Especially every time a disaster happens, it brings me back. Flashbacks from that day are still persistent, whether it’s the buildings falling, the dust, or the people’s faces. It’s never far from my mind.”