Transcript for Capitol police officer on siege: 'I was scared. I was absolutely scared'
That it would ABC news exclusive a capitol police officer who fought off the violent mob on January 6 is telling his story on camera. For the very first time officer Harry Dunne told our Chief Justice correspondent tear Thomas what he saw that day and how he's moving forward. There were so many calls on the radio. Priority help help somebody's trapped we need help shots fired. When capitol police officer Harry Dunn went to work on the morning of January 6. It felt like a normal day was the first moment. Did you begin to get a sense that something is off kilter here can we. Would till two. Give it helmets and riot helmets. And I was new but no sense at all hell could preclude court. Correct in the thirteen year veteran seen here marsh is the crowd of thousands. Closed in on the east side of the capitol. Easy CAC. Old people. Trunk legs confederate flags. And blue line flags don't tread only place pending the den and see officers fighting. With Steve pepper spray and smoke grenades desperately needs pepper balls. Being claimed by everybody slash span we've slip. With these people. Who were prepared. For a fight. They had investments. They have no body armor they had going two way radios. They handled tactical gear. The proved us they were ready to go when you see that level of preparedness. To death surprised you didn't scare you I was scared I was absolutely scared and his platform. I'm a big guy I'm 6% of them is giant person. And we had our guns out in and begin all of these people out there. There are intended. Mike. This and what's it mean I remember at one point has said. How was this going to end. Eventually the mob forces wait inside the capitol building. She's done confronting a group carrying a blue lives matter flat. We got dozens of officers. There are dozens of officers day. I have a moment where they. They came too when they realized like you know what are we doing. Like the income snapped out of the and they said. Now we're doing this for you we're doing this for you. And as what you guys kept walking by. The one put out his beds. And says it trust me understand we're doing this for you buddy. Instead of it's. Shows his Bennett's what you creek bill fellow officers can you got it was kidding me. You gotta be kidding me exhausted our Saddam tried reasoning with a large group of protesters approaching our Karl way he was guarding. Others told them if they want to get to hear you gotta go to me. And they did they just started talking to me they were saying out so Biden did not win the election. And nobody voted for him. So I took the bait. And I'd. Okay willow me I voted for Joseph Biden is my boat and I tell this is where an officer Dunn and touted the couple in the crowd. Began hurling the most violent racial slurs at him a black officer and his girlfriend sit on a thirteen meg this year. Today. The voted for Joseph Biden guys. Today everybody is a motive for so bud thanks to you. Sort of crowd joined everybody everybody joined him with a unit capital defending the capital. And some power raced seeped into that to everybody wants to say that. Who's about politics and everything. But it was a large number of people in that crowd. Data were racists that the people who were there to tell you why they were there. We're stopping this deal. According to them that would doors for Russ they're taught us a favor. Recorded those terrorists. You very precise users can use the word terrorist absolutely absolutely. It was insists. Mob or a bunch of thugs you know and they were terrorists. They tried to disrupt his country's democracy. That was good goal. You know what yell failed. Chief Justice correspondent Pierre Thomas an ABC news contributor and former FBI agent Greg Garrett joining us now for more. What stood out and moved you the most as you listen to officer Don. Well first of all he's speaking for himself and not to department weren't assuming known. I think this year chaos. The pandemonium. The medieval style fight it was going on there inside that inside that building. It's jarring. You can look in his eyes and seeing that he's still processing it all. And he is dumb founded. Angry. Bob this year otter bald faced naked races and release. And Brad what do you make of Dunn's account of how prepared are on prepared. Law enforcement was that day. They were shameful. And prepared. And I don't think it was a capitol police's. Office. Them themselves the need the chief and the people around the chief maybe in uniform. I don't think it was their fault I think it was a full of people above them I believe chief's son of former US capitol police she'd ask for more help. He asked for being National Guard. He was turned down in and he was told that the optics quote unquote war right the National Guard there. Nor initially Diddy and any other law enforcement that year. I mean it you just see this massive and breakdown. That was it was obvious. What was about the happen. End an eight you know it just is still out in front of all of this in in the first two things I thought after it was over is. It didn't need to happen. And the idea that there were actually sworn officers in that crowd that was part of that riot. It it just seeks volumes about how to bring more urged some people really are. And peer attorney general nominee Merrick Garland whose confirmation hearing is happening in the Senate Judiciary Committee. Right now he is said that he will establish an independent outside panel to investigate the capital siege. What's this status of the investigation right now and how could that panel helped. Well in terms of any panel by DOJ. Wouldn't let deck to be complicating because there is an ongoing criminal investigation right now. They have a dignified. Well over 200 suspects. I'm told that hundreds more. Are being looked at 200 or so. Two owners who have been charged. So this is the biggest most sweeping. FBI investigation in recent memory and perhaps the biggest ever. And just imagine trying to assign specific acts and find evidence spot all those suspects. And you're trying to build toward sedition cases have been some conspiracy charges brought. But he literally trying to identify everybody in that building particularly the people. Who committed acts of violence and vandalism. And separate and apart from that. You have to worry about. The various groups that have been cited. As to whether they pose a domestic terrorism Tara. And Brad you touched on law enforcement being part of that crowd we heard officer done in the inner view saying at least one of the rioters. Showed him a badge so what do we know about the extent to which law enforcement officers participated in this assaults right now and and how can not. Part of the story change the impact of this event when you look at it from an investigative perspective. So let's start with how many were there I don't really know. There have been publicly a number of officers that have been fired suspended. For various agencies across the country. But I think it really the most important element of this is. Why they felt justified. The literally break the law and potentially harm and or kill. LO police officers. Ended we really needed to get to the based rid of that that's the real key here. Because I don't feel like this ship is going to turn around. Until peoples' eyes are really open and they conducts naked except. The things hasn't been told like the election was a fraud except for a is just not true. But I will tell you that's a difficult thing didn't particularly when people are basically brainwashed. Is that they have to get disillusioned at some point. And I don't see that happening yet. Pierre Thomas and bragged -- great to have you both thank you.
This transcript has been automatically generated and may not be 100% accurate.