DENVER (AP) — A Colorado police officer who fatally shot a Black man holding what turned out to be a cellphone as police tried to arrest him will not be prosecuted, the district attorney announced Friday.

Officer Michael Dieck told investigators that he believed Kilyn Lewis, who was wanted in connection with a shooting in Denver, was holding a gun in his right hand and was about to fire at the officers in neighboring Aurora on May 23, District Attorney John Kellner said in a letter explaining his decision.

The other officers, who did not fire at Lewis, also described Lewis' actions as consistent with someone preparing to draw a weapon and otherwise fight with officers, Kellner said.

Lewis was shot as police, who had been surveilling him, moved in to arrest him in the parking lot of a condo building. In portions of body camera footage previously released by police, the officers, who appear to emerge from unmarked vehicles, can be heard shouting at Lewis to get on the ground. After taking a few steps next to his car and putting his right hand behind his back, Lewis raises his hands in the air, as if to surrender.

Kellner said Lewis showed his left hand but put his right hand in his right rear pocket, out of the view of officers. Lewis than raised his right hand holding an object, later identified as the cellphone, and Dieck fired one shot, he said.

Members of Lewis' family have called for Dieck to be prosecuted for murder. Since the shooting, relatives and other supporters have turned out at city council meetings asking for justice.

In a statement posted on social media, members of Lewis' family said they were “deeply disappointed and outraged” by Kellner's decision. They said they were not given any notice of it and have not had enough time to fully review his 20-page letter yet.

“This decision is not only a failure of justice but a message that the life of an unarmed Black man like Kilyn means nothing to the very system that is supposed to protect us,” they said.

The family asked supporters to join them at a rally before Monday's city council meeting.