ABC News January 8, 2023

'It broke me': Capitol officer describes recurring trauma of Jan. 6 attack

WATCH: ‘I thought I had it beat’: Capitol Police officer Harry Dunn on trauma from Jan. 6

Two years after the Jan. 6 attack, U.S. Capitol Police Officer Harry Dunn says he's still dealing with the emotional scars from that day.

Dunn, who struggled to defend the Capitol amid the hours of violence, described how his PTSD flared up this past fall.

"That moment in time hit me so hard is because I have made such good progress, to heal and be able to deal with these emotions and these feelings in a healthy manner and, you know, I could walk in and not be fazed by seeing somebody in a MAGA hat or a Confederate flag …. I made such good progress," Dunn said in an interview with ABC News Chief Justice Correspondent Pierre Thomas that aired Sunday on "This Week."

"But it was all just like out of nowhere just ripped away from me. And it wasn't a specific incident that caused it. Man, I thought I had this under control. I beat this," he said. "But no, it literally just came out of nowhere and it broke me, you know it broke me."

Oliver Contreras/Pool via Getty Images
U.S. Capitol Police officer Harry Dunn becomes emotional as he testifies before the House Select Committee investigating the January 6 attack on the U.S. Capitol, July 27, 2021 at the Canon House Office Building in Washington, D.C.

Nearly 140 officers from both the Washington's Metropolitan Police Department and the Capitol Police were injured when pro-Trump rioters stormed the Capitol, according to a recent estimate by the U.S. Capitol Police union.

While Dunn said he has more good days than bad, he said the insurrection is never far from his mind. He continues to work at the Capitol, making a point of walking through the Rotunda each day, marveling at all it means to him and the country, mindful that all it stood for could have been toppled two years ago.

MORE: Biden to award Citizens Medal to officers who defended Capitol on Jan. 6

On Friday, Dunn and fellow officers were awarded the Presidential Citizens Medal -- the nation's second-highest civilian honor -- from President Joe Biden.

Bill Clark/CQ-Roll Call, Inc via Getty Images, FILE
A video replay of the events of January 6th elicit tears on the faces of Sandra Garza, the companion of late U.S. Capitol Police Officer Brian Sicknick, and U.S. Capitol Police Officer Harry Dunn during the Select Committee to Investigate the January 6th Attack on the U.S. Capitol hearing in the Cannon House Office Building in Washington D.C., on June 9, 2022.
MORE: Capitol Police officer disputes claims that Oath Keepers were seen protecting him during Jan. 6 attack

Dunn, who testified before the House Jan. 6 committee, told Thomas that Donald Trump needs to be held responsible.

"I believe he should be held accountable for his actions or inactions of that day. … And he needs to be held accountable and that's why all eyes are on the Justice Department right now," he said. "Because they're the ones who can bring forth accountability. … There were criminal things that the former president has done. I don't see how you cannot hold him accountable for that day," he said.

ABC News' Ely Brown contributed to this report.