Prosecutors said Lockett lured Dean to a home he shared with his brother on Sandy Creek Drive in October 2016 under the guise that he was there for a drug transaction.

Several men then attacked Dean, beating him with a 2-by-4 and a crowbar for more than an hour in an effort to “show other gang members that working as a police witness would not be tolerated,” the DA’s office said.

Christopher Dean was tortured and killed by several men in the fall of 2016 after they discovered he had been a police witness in California. His body was left in the trunk of a car at an Atlanta MARTA station. Credit: Fulton County District Attorney's Office Credit: Fulton County District Attorney's Office

Investigators also said Dean was sodomized with a handle-like object and that seminal fluid was discovered inside his rectal cavity.

Rooks then drove from the scene to pick up two men —Green and Lamar Almon — who he paid to clean up the murder scene and dispose of Dean’s body, prosecutors said. After witnessing the “gruesome condition” of the body, however, the men decided instead to leave Dean’s body in the trunk of Lockett’s car at the MARTA station.

MORE: Brothers face murder charges after body found at MARTA station

“In my opinion, this murder — with its torture which included a brutal beating, sodomy with a wooden or metal object, penile sodomy by one or all of the defendants, shooting of the victim to the back of the head and the partial decomposition of the body — represents the most horrific death in our county in recent history,” DA Paul Howard said in a statement.

Lockett, Gibson, Clark, Rooks and Green will be sentenced April 19. Almon and Gibson’s brother Orlando have not gone to trial.

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