Human remains found near the Petaluma River were those of an adult woman, said Petaluma police Wednesday.

Official identification still awaited a check of dental records, said Petaluma Lt. Tim Lyons.

Her bones were found early Friday morning. They were on a remote section of undeveloped land on a peninsula stretching into the Petaluma River near downtown.

A transient boater told police he'd heard there could be a body near the McNear Peninsula and officers found scattered bones at about 2:30 a.m.

How the woman died also remained under investigation but Lyons said nothing has been found to suggest foul play.

It's possible the woman had been there since June.

The area had been mowed in June by a commercial mower and nothing was reported. Lyons said, however, that her bones were found near a large bush, which the mower had skirted.

"We're thinking after that. Although it could have been before and was missed," Lyons said.

McNear Peninsula extends more than half a mile into the Petaluma River from about Copeland and East D streets. It includes the city's two-acre Steamer Landing Park and an old livery stable restored and converted as the Petaluma River Heritage Center.

The Peninsula also includes about 10 acres of privately owned grass and scrub surrounded by shoreline. The body was found near the southern end.