CLARION, Pa.—A man has been jailed on third-degree murder and other charges for allegedly injecting a western Pennsylvania woman with a fatal dose of heroin before moving her body to her car to make it appear she had overdosed on her own.

Nineteen-year-old Devan Knapp's mother reported her missing Jan. 13 and her body was found in her car two days later on a road outside Clarion, about 60 miles northeast of Pittsburgh.

Online court records don't list an attorney for 29-year-old Shawn Ryan Carr, of Kittanning, who was also charged with drug delivery resulting in death, abuse of a corpse and other crimes.

Police say a witness saw Carr inject Knapp and when she didn't wake up, Carr put her in her car and drove it to where her body was found, putting a syringe in her lap.