Joshua Jackson was found dead in a Georgia storage unit last month, according to police. (Gwinnett County Police Department)(LAWRENCEVILLE, Ga.) — Police charged a fourth suspect on Wednesday in connection with the deaths of two men whose bodies were found in a Georgia storage unit last month.

Derrick Ruff and Joshua Jackson, both 25, were found with fatal gunshot wounds at a storage facility in Lawrenceville, Georgia, on March 17, nearly three months after their families reported them missing, according to the Gwinnett County Police Department.

The victims were last seen riding in a Ford Expedition on Dec. 18. Authorities recovered the vehicle two days later in Lawrenceville, about 30 miles northeast of Atlanta.

“As more suspects are identified, additional people could be charged. As of now, detectives are still trying to determine the link between the storage facility unit with the suspects and victims,” the department said in a statement. “The renters of the storage unit have been cooperative with this investigation.”

Officers said the deaths were being investigated as a double homicide, but murder charges had not been filed as of early Thursday, court records showed. Police said their killings could be connected to other deaths in the area.

Four men — Lesley Green, 30; Shabbazz Guidry, 24; Robert Carlisle, 32; and Justin Davis, 29 — have been named as suspects in the case, but only Green and Guidry are in custody.

Police said the motive appears to be gang-related.

Authorities arrested Guidry on charges of concealing the death of another on Wednesday. Carlisle, who is still on the run, and Green have also been charged with concealing the death of another, but police say they could face additional charges.

Davis, who faces charges of conspiracy to commit a crime, was also on the run as of Thursday. Police declined to offer details on his specific involvement.

“Davis’s whereabouts are currently unknown. His specific involvement in the crime is not being released at this time,” the Gwinnett County Police Department said in a statement. “Robert Maurice Carlisle is still on the run. He and Lesley Chappell Green are each facing two additional warrants for participating in criminal gang activity.”

It’s unclear if Green and Guidry, the two suspects in custody, have retained attorneys.

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