U.S. Capitol Police Sgt. Harry Dunn testifies during the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (Jim Lo Scalzo/Pool via AP)

WASHINGTON — “This is how I'm going to die, defending this entrance,” Capitol Police Officer Aquilino Gonell recalled thinking, testifying at the emotional opening hearing of the congressional panel investigating the violent Jan. 6 Capitol insurrection.

Officer Gonell told House investigators he could feel himself losing oxygen as he was crushed by rioters — supporters of then-President Donald Trump — as he tried to hold them back and protect the Capitol and lawmakers.

He and three other officers gave their accounts of the attack Tuesday, sometimes wiping away tears, sometimes angrily rebuking Republicans who have resisted the probe and embraced Trump's downplaying the day's violence by supporters who were challenging his election defeat.

Along with graphic video of hand-to-hand fighting, the officers described being beaten as they held off the mob that broke through windows and doors and interrupted the certification of Democrat Joe Biden's presidential win. The new committee is launching its probe with a focus on the law enforcement officers who protected them — putting a human face on the violence of the day.

Metropolitan Police Officer Michael Fanone, who rushed to the scene, told the committee — and millions watching news coverage — that he was “grabbed, beaten, tased, all while being called a traitor to my country.” Doctors later told him he'd had a heart attack.Daniel Hodges, also a D.C. police officer, said he remembered foaming at the mouth and screaming for help as rioters crushed him between two doors and bashed him in the head with his own weapon, injuring his skull.Capitol Police Officer Harry Dunn said one group of rioters, perhaps 20 people, screamed the n-word at him as he was trying to keep them from breaching the House chamber.Tensions on Capitol Hill have worsened since the insurrection, with many Republicans playing down, or outright denying, the violence that occurred and denouncing the Democrat-led investigation as politically motivated. Democrats are reminding people how brutal it was, and how the law enforcement officers who were sworn to protect the Capitol suffered serious injuries at rioters' hands.The officers detailed the horror of their experiences, their injuries and the lasting trauma as they begged the lawmakers to investigate the attack.“I feel like I went to hell and back to protect them and the people in this room,” Fanone testified.Pounding his fist on the table in front of him, he said, “Too many are now telling me that hell doesn't exist or that hell actually wasn't that bad. The indifference shown to my colleagues is disgraceful.”The lawmakers on the committee, too, grew emotional as they played videos of the violence and repeatedly thanked the police for protecting them.Illinois Rep. Adam Kinzinger, one of two Republicans on the panel, shed tears during his questioning. He said he hadn't expected to become so emotional.“You guys all talk about the effects you have to deal with and you talk about the impact of that day,” Kinzinger told the officers. “But you guys won. You guys held.”

CORRECTS IDENTIFICATION FROM HODGES TO DUNN - U.S. Capitol Police Sgt. Harry Dunn wipes his eyes during the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (AP Photo/ Andrew Harnik, Pool)

Rep. Liz Cheney, R-Wy., questions witnesses before the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday. Cheney was one of two Republicans on the panel.

Washington Metropolitan Police Department officer Michael Fanone testifies during the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (Jim Lo Scalzo/Pool via AP)

From left, U.S. Capitol Police Sgt. Aquilino Gonell, Washington Metropolitan Police Department officer Michael Fanone, Washington Metropolitan Police Department officer Daniel Hodges and U.S. Capitol Police Sgt. Harry Dunn testify before the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington on Tuesday.Photography by Associated Press

Rep. Adam Kinzinger, R-Ill., hugs U.S. Capitol Police Sgt. Aquilino Gonell after a House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (Jim Lo Scalzo/Pool via AP)

The U.S. Capitol is seen in Washington, early Tuesday, July 27, 2021, as U.S. Capitol Police watch the perimeter. Democrats are launching their investigation into the Jan. 6 Capitol insurrection. They’re beginning with a focus on the law enforcement officers who were attacked and beaten as the rioters broke into the building. It’s an effort to put a human face on the violence of the day. The police officers who are testifying Tuesday endured some of the worst of the brutality. The panel’s first hearing comes as partisan tensions have only worsened since the insurrection. Many Republicans have played down or outright denied the violence that occurred and denounced the Democratic-led investigation as politically motivated. (AP Photo/J. Scott Applewhite)

Washington Metropolitan Police Department officer Michael Fanone greets Rep. Sheila Jackson-Lee, D-Texas, as he arrives at the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (Bill O’Leary/The Washington Post via AP, Pool)

U.S. Capitol Police Sgt. Aquilino Gonell, from left, Washington Metropolitan Police Department officer Michael Fanone, Washington Metropolitan Police Department officer Daniel Hodges and U.S. Capitol Police Sgt. Harry Dunn are sworn in before the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (Chip Somodevilla/Pool via AP)

Rep. Jim Jordan, R-Ohio, left, Rep. Rodney Davis, R-Ill., and Minority Whip Steve Scalise, R-La., attend a news conference with House Republicans before the start of a hearing by a select committee appointed by House Speaker Nancy Pelosi on the Jan. 6 insurrection, at the Capitol in Washington, Tuesday, July 27, 2021. (AP Photo/Jacquelyn Martin)

Washington Metropolitan Police Department officer Daniel Hodges testifies before the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (Chip Somodevilla/Pool via AP)

Rep. Ann McLane Kuster, D-N.H., center, and Rep. Veronica Escobar, D-Texas, talk to U.S. Capitol Police Sgt. Aquilino Gonell after he testified before the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (Chip Somodevilla/Pool via AP)

U.S. Capitol Police Sgt. Aquilino Gonell, from left, Washington Metropolitan Police Department officer Michael Fanone, U.S. Capitol Police Sgt. Harry Dunn and Washington Metropolitan Police Department officer Daniel Hodges pose for a photo after they testified to the House select committee hearing on the Jan. 6 attack on Capitol Hill in Washington, Tuesday, July 27, 2021. (AP Photo/ Andrew Harnik, Pool)