YUMA, Ariz. — Authorities say a U.S. Marine from Standish found dead this week in a southwest Arizona irrigation canal had a gunshot wound to the head.

Yuma police officials announced Friday that they’ve assumed the investigation into the death of 22-year-old Cpl. Joshua Barron.

His civilian-clothed body was discovered Monday in a Yuma canal by a farmer. Barron was reporting missing March 16 when he failed to show up for work.

Barron was stationed at Marine Corps Air Station Yuma, where he was a Harrier jet mechanic. He lived off base.

Yuma County Sheriff’s officials had said Tuesday that foul play wasn’t suspected. Yuma police said Friday that circumstances surrounding Barron’s death remain under investigation.

An autopsy was completed Wednesday by the Pima County Medical Examiner’s Office and results still are pending.