Sergeant involved in Breonna Taylor's death, her boyfriend recount details in newly released interviews

New audio has emerged from the investigation into the death of Breonna Taylor, who was shot at home by police during the execution of a no-knock warrant.

Newly released interviews with police and her boyfriend, Kenneth Walker, who spoke to authorities hours after he survived the encounter that killed Taylor at their home on March 13 reinforce that the couple had no idea who was attempting to break into the apartment that night.

In the audio, which was first obtained by NBC News, Walker is heard telling Public Integrity Unit officials, who investigate officer-involved shootings, why he fired a shot inside their Springfield Drive apartment.

"It's a loud boom at the door. First thing she said was, 'Who is it?' No response," he said.

"We both get up, start putting on clothes, another knock at the door. She's like, 'Who is it?' Loud, at the top of her lungs. No response," Walker, 27, said. "I grab my gun, which is legal, like I'm licensed to carry, everything. I've never even fired my gun outside of a range. I'm scared to death."

After another knock at the door, Walker said Taylor yelled "at the top of her lungs," but there was "no response, no anything." Walker added that he and Taylor put on clothes to answer the door, which then came "off the hinges."

"I just let off one shot. Like, I still can't see who it is or anything. So now the door's, like, flying open," he continued. "I let off one shot, and then all of a sudden there's a whole lot of shots and we like we both just dropped to the ground."

Taylor, 26, who worked for Louisville Metro Emergency Medical Services as a licensed EMT, was killed when police returned fire.

Officers had executed a no-knock entry "due to the nature of how these drug traffickers operate," according to the arrest warrant obtained by ABC News.

Taylor was accused of accepting USPS packages for an ex-boyfriend whom police were investigating as an alleged drug trafficker who used her address, according to the warrant.

Newly released video showed the moment Walker was arrested in the parking lot of their apartment. Initially, authorities charged him with attempting to kill police officers, but those charges were dismissed.

On Thursday, ABC News obtained Walker's audio statement to police from his attorney. His lawyer also released another audio interview, conducted March 25, with the highest-ranking officer who was at the couple's front door when Taylor was shot to death.

In the audio, Walker could be heard expressing concern for the officer he shot. "[Is] the police officer that got hit OK?" he says in the audio.

At one point he says that he aimed down when he fired.

"Yeah, like, because I wouldn't, of course ... I don't need to kill anybody. ... If I could just get you out of here just by you hearing that," he said.

When investigators asked Sgt. Jon Mattingly, who with officers Myles Cosgrove and Brett Hankison used a ram to break open the door and were involved in Taylor's shooting, whether he could remember the name of the target on the search warrant, he said "not offhand."

Mattingly also said during the interview, which happened 12 days after the fatal incident, that the officers did not initially announce who they were when they started banging on the door just after midnight.

"The first banging on the door, [we] did not announce," he said. "I think after that we did. ... After that, each one of them said, 'Police, come the door. Search warrant. Police, search warrant.'"

Walker, however, told police that he didn't hear police saying this.

"All can hear is a knock at the door," he said. "Even if somebody was saying something on the other side, you probably couldn't hear them. But as loud as we were screaming to say who it is, I know whoever will be on the other side of the door could hear us."

Once inside Taylor's home, Mattingly recalled, "I could see enough to see a male on the right. A female on the left. Could identify their faces."

"But I could actually see the handgun in his hand," he said. "I remember seeing the barrel of that soon as we turned that corner."

The lawsuit, filed in Jefferson District Court on April 27 by attorneys Sam Aguiar and Lonita Baker, seeks damages for battery, wrongful death, excessive force, negligence and gross negligence. Hankison, Cosgrove and Mattingly are named as defendants in the suit filed by Aguiar and Baker on behalf of Taylor's mother, Tamika Palmer.

"The recorded statements of Kenny Walker and Sergeant Jonathan Mattingly released today clearly reveal that there has been a conspiracy to cover up Breonna's killing since day one," Aguiar, Baker and their co-counsel, renowned civil rights attorney Ben Crump, said in a statement Thursday. "They substantiate what we've maintained all along: that police did not announce themselves when they broke into the residence with a battering ram and released a shower of gunfire into the apartment, killing Breonna, that the warrant and its execution were based on erroneous information and that Louisville police actively worked to cover up Breonna's brutal murder."

Hankison, who fired the shots that killed Taylor, was terminated from the Louisville Metro Police Department in late June, with Police Chief Robert J. Schroeder writing in a letter that he "displayed an extreme indifference to the value of human life" by firing 10 shots upon entering Taylor's home unannounced.

ABC News' Christina Carrega contributed to this report.

This report was featured in the Friday, July 10, 2020, episode of “Start Here,” ABC News’ daily news podcast.

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