PAULDING COUNTY, Ga. — A man admitted to a double murder more than 16 years later after “a guilty conscience got the best" of him, according to authorities in Paulding County.

The bodies of 21-year-old Shad Andrew English and 19-year-old Dennis Jeffrey Jackson were found in the trunk of a burning car on the side of Interstate-20 in 2002. An autopsy determined they had been shot to death, but the investigation never turned up anything leading to a suspect.

The Paulding County Sheriff’s Office, however, announced on Thursday the arrest of Andrew Shadrix. According to the sheriff’s office, Shadrix has confessed to the murders.

Police said in a release that “investigative leads that were developed in other cases” led to the cold case being reexamined last year. They could not elaborate on those leads.

Shadrix confessed on Wednesday, authorities said.

“This is a case where perseverance paid off and a guilty conscience got the best of the suspect,” Paulding County Sheriff Gary Gulledge said. “We are glad the Jackson and English families will now have closure knowing that their sons’ murderer is in custody.”

The reopened investigation determined the murders had been drug-related, and occurred at a home in Douglasville that has since been torn down for unrelated reasons.

Shadrix is already in state prison on a felon in possession of a firearm conviction. His earliest possible release was July next year before the new charges were filed.

He has been charged with two counts of malice murder. Police said more charges are likely.

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