Oct. 8 (UPI) -- Joshua Brown, a key witness in the murder trial where Amber Guyger was convicted Wednesday, was killed days later in a drug deal, police said Tuesday, adding that a suspect is in custody.
Guyger was sentenced to 10 years in prison Wednesday for killing Jean Botham, a 26-year-old black accountant, in his apartment last year. Guyger, an off-duty police officer who lived in the same apartment complex, said she mistook Jean's apartment for her own and thought he was an intruder.
Brown, 28, a key witness in the trial who lived in the same South Side Flats apartments in downtown Dallas, was shot to death Friday, fueling speculation he had been killed in retaliation for his testimony.
However, the Dallas Police Department said Tuesday that Brown was killed in a drug deal.
"There has been speculation and rumors that have been shared by community leaders claiming that Mr. Brown's death was related to the Amber Guyger trial and somehow the Dallas Police Department was responsible," Avery Moore, an assistant chief who oversees criminal investigations said at a news conference. "I assure you that is simply not true."
Moore added that police confiscated 12 pounds of marijuana from Brown's apartment along with $4,157 in cash and 149 grams of THC cartridges.
Authorities also said at the news conference that Jacquerious Mitchell, 20, one of three suspects sought on capital murder charges in Brown's killing, is in custody at a hospital.
The other two suspects identified as Michael Mitchell, 32, and Thaddeous Green, 22, remain at large.
All three suspects had traveled from Alexandria, La., to buy drugs from Brown in Dallas apartment complex parking lot, according to authorities.
Jacquerious Mitchell told police Green shot Brown twice in the lower body after he got into an altercation with him, Moore said.
Then, Mitchell alleges that Brown shot him in the chest and he heard two more gunshots.
All three suspects fled the scene after Green took Brown's backpack and a gun involved in the shooting, Moore said. Jacquerious Mitchell was dropped off at a hospital, assistant police chief said.
Michael Mitchell is suspected of being the getaway driver.
Still, Lee Merritt, representing Brown's family, is calling for an independent investigation.
"On behalf of the family of Joshua Brown, this office encourages the Dallas Police Department to turn over this murder investigation to an alternative investigative agency," a statement Merritt tweeted from the Brown family said. "A cloud of suspicion will rest over this case until steps are taken to ensure the trustworthiness of the process."