The son of an Alabama prosecutor has been shot to death on an interstate.

News outlets report that 20-year-old Nicholas Sloan Harmon was found with a fatal gunshot wound inside a car at an exit off Interstate 20 on Tuesday night.

St. Clair County Coroner Dennis Russell says Harmon was the son of District Attorney Lyle Harmon, who serves as the chief prosecutor in the county just east of Birmingham.

Authorities haven’t said what might have led to the shooting, which happened in Moody.

Al.com reports a suspect was arrested in nearby Pell City early Wednesday after a search that lasted hours.

The victim’s father was appointed district attorney earlier this year after the former prosecutor joined a state appeals court.