Former Dallas police Officer Amber Guyger can be heard telling a 911 dispatcher she shot Botham Jean after she entered his apartment by mistake, in a recording obtained by WFAA-TV (Channel 8)

In the nearly six-minute recording, which has not been officially released, a panicky-sounding Guyger is heard asking for assistance and apologizing to Jean and telling him help is on the way.

Guyger was off-duty but in uniform when she shot Jean once in the chest about 10 p.m. Sept. 6. Jean, 26, had been watching football on his couch.

Guyger turned herself in to Kaufman County authorities three days after the shooting and was charged with manslaughter, which drew widespread outrage from people who said that wasn't severe enough. In November, Guyger was indicted on a murder charge.

Her trial is scheduled to begin in September.

A law enforcement official told The Dallas Morning News in the days after the shooting that Guyger called 911 in tears. The official said Guyger repeatedly said "I thought it was my apartment" and apologized to Jean.

The 911 recording begins with Guyger frantically telling the dispatcher that she needs police and emergency medical services to come to the apartment.

Warning: This audio contains explicit language

"I'm an off-duty officer. I thought I was in my apartment and I shot a guy thinking he was — thinking it was my apartment," Guyger says.

"I'm gonna lose my job," she says at one point after the dispatcher tells her help is on the way. "I'm going to need a supervisor."

Guyger also can be heard talking to Jean, apologizing to him and trying to reassure him help is coming.

"Oh my God, I'm done. I didn't mean to, I didn't mean to, I didn't mean to," she says. "I'm so sorry. Hey, bud."

Amber Guyger was indicted Nov. 30 for murder in the shooting death of Botham Jean. Guyger shot and killed Jean Sept. 6 when she said she mistook his apartment for hers and thought he was a burglar. Guyger, a Dallas police officer at the time, was off-duty but in uniform when she killed Jean. (Mesquite Police Department, via Instagram)

Throughout the call, Guyger repeatedly says she thought she was in her own apartment, which was one floor below Jean's.

Guyger has maintained since the shooting that she mistook Jean's apartment at the South Side Flats for her own.

"I could have sworn I parked on the third floor," Guyger says in the call.

According to an arrest warrant affidavit, Guyger told authorities she mistakenly parked on the fourth floor instead of the third and inserted her key into Jean's door, which was slightly ajar.

Details about whether the door was slightly open — an account Jean's family has questioned — are not included in the 911 audio.

In the weeks after the shooting, the city of Dallas refused to release a copy of the 911 call at The Dallas Morning News' request. An attorney for the city said then that the Dallas Police Department and Dallas County district attorney's office had asked state Attorney General Ken Paxton to allow them to withhold the call.

The call was among a number of records police and prosecutors have tried to avoid releasing, including Guyger's personnel file, her clock-in and clock-out times the day of the shooting and Jean's autopsy.

WFAA's online report did not explain how it obtained the recording.

About two and a half minutes into the recording, the 911 dispatcher asks Guyger for a gate code, which she does not know, so first responders can get in.

Throughout the call, Guyger seems frantic and exasperated, at times sounding short of breath and tearful.

"I — how the [expletive], how did I — how did I — I'm so tired," Guyger says right before first responders appear and she calls them over. "I'm off-duty. I thought they were in my apartment. I thought this was my floor," Guyger says before the call disconnects.

Paramedics rushed Jean to Baylor University Medical Center at Dallas, where he was pronounced dead.

Dallas Police Chief U. Renee Hall fired Guyger on Sept. 24 — the same day Jean was buried in a cemetery by the sea in St. Lucia, where he grew up.