SAVANNAH — A coastal Georgia commissioner was shot in the head before he drowned in the Frederica River, where his body was discovered next to a docked boat, but officials have not determined whether it was homicide or suicide, the county coroner said Thursday.

The body of Glynn County Commissioner Tom Sublett, 52, was found early Tuesday hours after he failed to return home from a Monday night poker game he regularly played with friends. Police in the county along the coast about 60 miles south of Savannah have said they suspect foul play but released few details.

Coroner Jimmy Durden said the cause of death was determined by an autopsy at the Georgia Bureau of Investigation crime lab in Savannah. But he said he was still awaiting a ruling on the manner of death, as in whether it was homicide or suicide. So far police have been investigating the case as a homicide.

Despite the gunshot, evidence showed it was the water that ultimately caused Sublett’s death, the coroner said.

“If he did have a gunshot wound to the head before he went in; he was not dead because he had water in his lungs” when the body was found, Durden said.

Glynn County Police Chief Matt Doering was referring calls to the GBI, which has taken the lead in the investigation. Mike McDaniel, agent in the charge of the GBI’s Kingsland office, declined to comment.

The news of how Sublett died came as his mourning family and friends made arrangements to say farewell over the weekend. Visitation for the commissioner was scheduled for Friday evening followed by his funeral Saturday morning at St. Mark’s Episcopal Church in Brunswick, where Sublett was a senior warden.

Sublett, who sold commercial real estate, was wrapping up his first and only term on the seven-member Glynn County Commission. He decided not to seek re-election to another four years on the commission after his term ended Dec. 31.