A witness who testified in the murder trial of a former Dallas police officer is dead and police are trying to piece together what happened. Joshua Brown was killed Friday night, just a week after he testified about the murder of his former neighbor, Botham Jean. Right now there are no known suspects or motive. The Dallas Morning News reports:

The Police Department confirmed Sunday afternoon that the 28-year-old Brown was the victim whom officers found about 10:30 p.m. Friday with multiple gunshot wounds to his lower body. Police spokesman Sgt. Warren Mitchell said Saturday, before Brown had been publicly identified, that the victim died at Parkland Memorial Hospital.

The timing of Brown’s death has raised public speculation about whether the shooting was tied to his testimony.

NBC  News adds:

Brown, 28, lived across the hall from Jean, 26, at the Southside Flats apartment building in Dallas, where (Amber) Guyger fatally shot Jean last year when she mistakenly entered his apartment instead of her own.

In a closely watched trial, Guyger, 31, was found guilty of murder Tuesday and sentenced to 10 years in prison. Brown helped the prosecution piece together the events of Jean’s murder that ultimately led to Guyger’s conviction.

Brown’s death has garnered attention from some of the Democrats running for president.

And Senator Elizabeth Warren wrote:

“I’m heartsick for Joshua Brown‘s family and friends. He bravely stepped forward and testified to bring some justice for Botham Jean, and peace for his family. We need answers—and Joshua Brown and his family need justice.”

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