A 16-year-old has admitted to shooting and stabbing a 13-year-old boy multiple times, DeKalb County police said.

Officers divulged their findings in the case at a court hearing Tuesday, including disturbing items found in the suspect’s bedroom.

Police said Troy Westberry told them he killed Marquis Overstreet in self-defense July 4. Overstreet was shot twice and stabbed 23 times in a wooded area on Biffle Downs Road in Stone Mountain.

Detectives said they found the murder weapons in Westberry’s bedroom, along with satanic pentagrams on the wall and a mummified animal under his bed.

Marquis’ mother, Keisha Langhorne, grimaced in court as she heard the details of her son’s killing.

“Sick. That just shows that there’s evil in the world,” she said. “I just want justice served for my son.”

Detectives said a teen saw Westberry and a boy walking toward the wooded area. When Westberry returned alone and the teen asked about the boy, Westberry said, “He’s in the woods bleeding with his eyes open,” Detective Bruce Brueggeman testified.

The evidence didn’t surprise a pastor who taught an anger management class Westberry was kicked out of.

“There was already evidence of him with so-called satanic worship,” pastor Bennie Foster told Channel 2’s Tom Jones.

Police said Westberry told them Overstreet tried to rob him of some cigarettes, but he took the gun away and shot and stabbed him. Overstreet’s loved ones don’t believe the story and highlighted the viciousness of the crime.

“You don’t stab nobody 25 to 30 times. You don’t do that,” Overstreet’s friend, Wale Brown, told Jones.