Updated at 1:30 p.m.: Revised to include statements from the police chief and other reactions.

Dallas police Officer Amber Guyger, who fatally shot 26-year-old Botham Jean in his Cedars apartment, was fired Monday — days after Police Chief U. Renee Hall said doing so would compromise the criminal investigation.

Amber Guyger (Kaufman County Sheriff's Office)

Police said in a news release that Hall fired Guyger after an internal investigation found the officer had engaged in "adverse conduct" when she was charged with manslaughter three days after the shooting.

Guyger's firing was lauded by the mayor — who called it "the right decision in the interest of justice" — and others who have been calling for her termination for weeks. Guyger has been on administrative leave since the shooting and is free, as she awaits trial, on a $300,000 bond.

Guyger shot Jean, her upstairs neighbor, the night of Sept. 6. She told authorities she mistook his apartment for her own and believed Jean, who was unarmed, was a burglar. Lee Merritt, an attorney for Jean's family, has cast doubt on Guyger's version of events.

Hall's decision to fire Guyger came after widespread calls for action and protests. Her employment status even became an issue in the U.S. Senate race between Sen. Ted Cruz and Rep. Beto O'Rourke. The latter, a Democrat, had called for her firing, while Cruz had said O'Rourke was rushing to judgment.

Guyger is allowed to appeal the decision under civil service rules, police said.

The announcement of Guyger's firing came shortly before Hall stepped into a City Council Public Safety & Criminal Justice Committee hearing. The only discussion of the firing during the meeting came when council member Kevin Felder said he had heard Guyger had been fired and asked the chief to confirm.

"That is a true statement," Hall said, without elaboration.

Hall's decision to fire the officer seemed to contradict statements she had made in recent days about why she hadn't yet fired Guyger.

The chief said at a town hall on Tuesday that she couldn't fire Guyger before an internal investigation was completed because of federal, state and local laws. She didn't specify to which laws she was referring. Hall's chief of staff, Thomas Taylor, had said the internal investigation was on hold until a criminal investigation into Guyger was complete.

On Thursday, Hall released a statement saying she didn't want to risk interfering with a criminal investigation by making a decision about Guyger's employment.

"As an employer, DPD can compel Officer Guyger to provide a statement during a DPD administrative investigation and those statements given to DPD could potentially compromise the criminal investigation," Hall said in a written statement.

The Dallas Police Department turned over the investigation to the Texas Rangers shortly after the shooting. The Dallas County District Attorney's office is also conducting its own investigation.

Those investigations aren't complete, but Hall said Monday police were notified that a "critical portion" of the criminal investigation — the part that she said could've been compromised by an internal investigation — had been concluded over the weekend.

"As a police chief, my job is to ensure the highest level of integrity in this investigation, and that is what I did," she said. "I waited until the critical portion of this investigation was complete."

Guyger's attorney Robert Rogers said in a written statement that Hall "bowed to pressure from anti-police groups and took action before all of the facts had been gathered and due process was afforded."

"That's not the way our system of justice should work," he said. "It is important for all parties and the integrity of the justice system that a full and fair investigation be allowed to reach its conclusion before decisions such as this are made."

Rogers said his client is "completely devastated by what happened." The shooting, he said, was "a tragic mistake and words can never express our sorrow for the pain being suffered by those who knew and loved Botham Jean."

Michael Mata, president of the Dallas Police Association, said Monday he had no idea Guyger was going to be fired until Hall's statement was released. He said he was "perturbed" by the news, and confused by what he called "short-sightedness and short cuts" leading to her firing.

"Four days ago, she said she couldn't fire her because of the investigation, and now, four days, later you can?" Mata said. "Just be honest with the public. There is a process in place that not only affords an officer due process but allows the department to have security if and when an officer attempts to get their job back."

But Mayor Mike Rawlings said in a prepared statement that Hall "made the right call" in firing Guyger.

Dallas police Chief U. Renee Hall spoke at a Public Safety Committee meeting at City Hall on Monday, moments after it was announced that Amber Guyger had been fired from the department. (Louis DeLuca / Staff Photographer)

"I have heard the calls for this action from many, including the Jean family, and I agree that this is the right decision in the interest of justice for Botham Jean and the citizens of Dallas," he said in the prepared statement. "The swift termination of any officer who engages in misconduct that leads to the loss of innocent life is essential if the Dallas Police Department is to gain and maintain the public trust."

Attorneys for the Jean family said Jean's parents got a call from Hall on Sunday, in which she told them she intended to fire Guyger and explained the delay.

Merritt said that while the delay was frustrating, he's glad the chief waited until all the statements made about Jean's killing had been thoroughly investigated.

He said the trial of former Balch Springs officer Roy Oliver was complicated by complaints that the officer's Fifth Amendment rights had been violated by his department's decision to fire him just days after he shot into a car full of teenagers and killed 15-year-old Jordan Edwards.

The Jean family was satisfied with both the termination and explanation, the attorneys said, but they will continue to fight for a murder charge and appropriate sentencing.

"When you fire someone, it's an implicit admission that what they did is wrongful," Merritt said. "The inference is hard to miss."

Activist Dominique Alexander, who has led protests over Jean's shooting, said Guyger's firing was a positive step. But he said he was "not a fan of" what he perceived to be special treatment for Guyger during the investigation.

"The community cannot start to heal until this officer is held [accountable] and justice is served," Alexander said. "The first step in the process of it is making sure she's off taxpayer dollars."

Staff writers Sara Coello and Robert Wilonsky contributed to this report.