Police in Dallas have identified a man killed in a weekend shooting as a key witness in the murder trial of a white Dallas police officer who fatally shot her black neighbor.

Police said Sunday Joshua Xavier Brown, 28, was found Friday night in the parking lot of an apartment complex with multiple gunshot wounds. Brown was pronounced dead at a hospital.

Brown testified in the murder trial of Amber Guyger, who was convicted last week in the September 2018 slaying of Botham Jean. As part of Brown's testimony, he said he had also walked to the wrong floor of his apartment building at times.

Brown lived across the hall from Jean.

According to her trial testimony, she mistook Jean's apartment for her own one floor below and shot him after pushing open his unlocked door and thinking he was a burglar.

She was sentenced to 10 years in prison last week for killing Jean.

Dallas homicide detectives are seeking the public's help in identifying suspects in Brown's death.

There's a $100,000 reward for information to find the shooter.