Divers recovered a body from the Petaluma River early Sunday police believed to be that of an elderly man missing since Friday.

The body was the fourth authorities have recovered in and around the city's waterways since August. Police officials have said none of the cases have clear marks of foul play or violence, and one was a confirmed suicide. In the most recent case, the elderly man has lived aboard a boat in the marina for a number of years, and a concerned neighbor called police at 1:50 p.m. Friday after thinking it odd the man didn't appear to be home, Petaluma Police Sgt. Marty Frye said.

Police searched the river banks and checked local hospi?tals, but found no trace of the man.

A dive team from the Napa County Sheriff's Office entered the water early Sunday and at 7:46 a.m. found a man's body submerged in the boat slip area of the marina, Frye said.

Sonoma County coroner staff will confirm the man's identity and determine how he died. The Police Department will withhold the missing man's name until that time, Frye said.

The death doesn't appear suspicious, but officers were interviewing witnesses and investigating the matter.

Of the other recent deaths, two involve people police suspect were transients, although it wasn't clear Sunday if the coroner's office has confirmed their identities and how they died.

Still, the deaths prompted concerns from police and social service agencies about what should be done in response.

On Sept. 12, a dog walker found the body of a man in Willow Brook Creek near several homeless camps on the north end of town.

Following a tip, police located a woman's skeleton Aug. 16 in an undeveloped area of the McNear Peninsula near downtown.

Police determined a man found Sept. 18 below the D Street bridge had committed suicide.