Five Atlanta gangbangers were convicted this week of torturing and killing a former police informant in “the most brutal murder” in the city’s recent history, according to prosecutors and a new report.

The men — members of the Gangster Disciples street gang — murdered Christopher Dean, 33, in October 2016 after learning he was once a police witness in California, the Atlanta Journal-Constitution reported.

Christopher Lockett, 30, had invited Dean to the home of brothers Xavier Gibson, 23, and Orlando Gibson, 30 — where Dean expected that he and Lockett would complete a drug transaction, the Fulton County District Attorney’s Office said in a statement.

But instead, Dean was brutally beaten with a two-by-four and a crowbar and sodomized with a handle-like object — and seminal fluid was discovered in his rectal cavity, prosecutors said. The savage crew then allegedly shot Dean twice in the back of the head.

The cold-blooded slaying was an effort to show other gang members that any police informant activity would not be tolerated, prosecutors said.

Lockett had paid Jasper Green, 27, and Lamar Almon, 25, to clean up the gruesome scene and burn Dean’s body as well as his car — but the body was in such a grisly condition that they instead dumped the corpse in the trunk of his car and left the vehicle in the parking lot of the Hamilton E. Holmes subway station, prosecutors said.

Atlanta police discovered the body, and seven suspects were arrested, the DA’s office said. Lockett, Xavier Gibson, Quatez Clark, 21, Joshua Rooks, 27, and Jasper Green, 27, were convicted Monday of murder, participation in criminal street gang activity and other related felonies, according to prosecutors.

They will be sentenced on April 19. Orlando Gibson and Almon will be tried before a Fulton County Superior Court jury at a later date.

“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,” Fulton County DA Paul L. Howard Jr. said in the statement.