DETROIT (WWJ/AP) – Authorities have charged two men and one woman in the abduction and killing of a 13-year-old boy who was the subject of an Amber Alert in Detroit.

Wayne County Prosecutor Kym Worthy said Thursday that 45-year-old Gregory Walker is accused of choking Deontae Mitchell to death with help from his girlfriend, Lillian Roberts, and 26-year-old Earnest Coleman.

Gregory Walker at left; Lillian Roberts, center and Earnest Coleman. (Booking photos)

Gregory Walker at left; Lillian Roberts, center and Earnest Coleman. (Booking photos)

All three face murder, unlawful imprisonment, kidnapping, torture and felony firearms charges. Coleman had been charged with kidnapping last weekend.

Deontae Mitchell (police handout)

Deontae Mitchell (police handout)

A cousin told police that Deontae disappeared a short time after he picked up some money dropped by “a drunk man” outside an east side market where the pair had been riding their bikes the night of May 31.

Prosecutor Kym Worthy said Thursday that Deontae rode away with about $70 of cash but later was found by the trio.

Police the next day released chilling surveillance video showing Deontae being pursued by a man, grabbed, and forced into a car.

The boy’s body was found June 2, hidden in tall grass in a vacant lot at Harper and Baldwin in Detroit.

Later that day, Walker and Roberts were arrested at Toledo hotel; and Coleman was taken into custody in Detroit.

At a news conference, Worthy said Deontae was a “victim” regardless of the circumstances.

“This whole thing is hard to believe,” Worthy told reporters. “This case shocked us all, and there’s not a whole lot that shocks a seasoned prosecutor.”

“So, again, some things you just cannot explain, and we in the criminal justice system just have to make sure that we hold the people responsible criminally.”

Mitchell, Roberta and Coleman were each ordered held without bond at an arraignment Thursday.

A fourth person wanted in connection with the case, 51-year-old Roy Portis, was arrested at his home last Friday. It’s unclear what charges he might face or how he might have been connected to the crime.

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