Joshua Brown, 28, was a witness in the murder trial of Amber Guyger.

DALLAS — Updated at 9:55 p.m. Sunday. This story has been updated throughout.

A former neighbor of Botham Jean who testified during the trial of former Dallas police officer Amber Guyger was gunned down Friday night at an apartment complex.

The medical examiner on Sunday officially identified Joshua Brown, 28, as the victim of the shooting. The medical examiner’s office said the autopsy has been conducted.

Dallas police issued a statement Sunday afternoon saying that Brown was shot multiple times in the lower portion of his body. Dallas County Judge Clay Jenkins tweeted that Brown was not shot in the “mouth or head.” Jenkins vowed the city and the county would "work to ensure a transparent and thorough investigation of the murder of Joshua Brown."

Dallas Police Chief U. Renée Hall said in a statement late Sunday afternoon that there are no “suspects or motives” in Brown’s killing.

“We are committed to solving this case and will work diligently to apprehend the individuals responsible for Brown’s death,” the chief’s statement said.

Lee Merritt, an attorney representing the Jean family, tweeted Saturday that he had spoken with Brown’s mother and she was “devastated.”

Merritt initially tweeted that Brown had been shot in the “mouth and chest.” He tweeted two hours later that where Brown was shot was in dispute and that he had heard from a witness that the wounds were to Brown’s “buttocks and side.”

Merritt also said Brown’s mother told him that Brown had “no known enemies.” He said Brown was ambushed as he was exiting his car at his apartment.

According to police, the shooting occurred around 10:35 p.m. at the Atera Apartments near the 4606 block of Cedar Springs Road.

Police say when they arrived at the complex, they found a man in the parking lot with gunshot wounds. Brown was transported to the hospital where he was pronounced dead.

After Friday night’s shooting witnesses told police they heard several gunshots and saw a silver four-door sedan leaving the parking lot after the shooting. They were not able to provide a physical description of any possible suspects.

Brown was involved in a prior shooting

WFAA has also learned that Brown was a victim of gun violence last year.

Last November, Brown was shot and another man was killed outside the Dallas Cabaret strip club on Walnut Ridge Street in Northwest Dallas.

Kendall Deshonn Morris has been indicted on charges of murder and aggravated assault in connection with the incident. He is currently out on bond.

The Dallas Morning News wrote a story on the incident last December.

The DMN cited an arrest affidavit stating that Morris and another man were at the club celebrating a birthday and encountered Brown at the strip club.

The other man wanted to fight Brown and the two men fought in the street, the News reported. When Brown and his friends attempted to leave, Morris pulled a gun out of a car and handed it to another man, the story said.

Nicholas Shaq'uan Diggs was killed and Brown was hit in the foot.

Brown was a witness in the murder trial of Amber Guyger, appearing on the stand on Sept. 24. He lived across the hall from Botham Jean.

The men met earlier in the day on Sept. 6, 2018, after an apartment manager knocked on Brown's door and told him about a noise complaint.

Later that night, Brown was returning home when he heard loud voices as he walked down the hall.

He said it sounded like "two people meeting each other by surprise" but couldn't make out what the voices were saying, but heard gunshots.

Brown choked up on the witness stand and took a break after testifying about hearing Jean singing every morning across the hall.

On Sunday, Merritt acknowledged that the 2018 shooting made Brown nervous to testify.

“He was concerned that someone would try and come finish the job,” Merritt said.

Despite his reluctance to testify, Merritt said it was his plan to ask Brown to take the witness stand again.

“When we move forward with our civil trial, he was one of the first people we planned on calling,” Merritt said. “And now is no longer available.”

Speaking about the investigation into Brown's murder, Merritt said that "there is no link to law enforcement or to the trial directly, but it’s something worth looking into."

Dallas police ask anyone with information to contact Detective Jacob White at 214-671-3690 or via email at jacob.white@dallascityhall.com. Please refer to case No. 202433-2019.

Crime Stoppers is offering to pay up to $5,000 for information leading to an arrest. Crime Stoppers can be reached at 214-373-8477.

Nationally known civil rights activist Shaun King tweeted that a $100,000 reward is now being offered in Brown’s death.

Dallas leaders react

Many Dallas leaders tweeted out their thoughts on Brown's death over the weekend. Below is a running list of statements and reactions that will be updated accordingly.

Editor's note: A previous version of this story stated Joshua Brown was 27 years old. This has been corrected to 28 years old.

This is a developing story and will be updated. For more breaking news coverage, download the all-new WFAA app.