According to Moore, Jacquerious Mitchell said that when he exited the vehicle, Brown ordered him to get back in, then shot him in the chest.
Brown, who lived on the same floor as Jean, testified that on the night Jean was killed, he heard what sounded like "two people meeting by surprise" and then two gunshots.
Lee Merritt, who was an attorney for Jean's family and for Brown's family called his death "suspicious".
He stated during the press conference, "The rumors shared by community leaders that Mr".More news: Samsung flags 56% decline in operating profit in Q3
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"I assure you that is simply not true", said Assistant Chief of Police Avery Moore, during a news conference that was posted on the department's Facebook page. "I encourage those leaders to be mindful of their actions moving forward because their words have jeopardized the integrity of the city of Dallas as well as the Dallas police department".
One of the suspects, Jacquerious Mitchell, is in police custody. Jacquerious Mitchell, 20, has been arrested and will be charged with capital murder, Moore said. Jacquerious was taken to a local hospital where he remains in police custody.
Police say Joshua Brown was gunned down in a botched drug deal. In addition to him, there are two fugitives (Thaddeous Charles Green and Michael Diaz Mitchell) on the lamb, who police believe have already left the state.
Michael Mitchell dropped Green off at an unknown location, then took Jacquerious Mitchell to Promise Hospital of Dallas.
The conversation "escalates into physical altercations", Moore said. Police searched Brown's apartment after his killing and found 12 pounds of pot and about $4,000 in cash, he said.
The assistant chief chastised those who've connected Brown's death to his testimony in the Guyger trial. "Brown's death was related to the Amber Guyger trial and that DPD was responsible are false", Moore said. "There is a lack of credibility that the Dallas Police Department now has and, frankly, it's not just among brown and black communities". The former officer was found guilty of murder and sentenced to 10 years in prison last week.