Police Wednesday were investigating a body found under the D Street bridge in downtown Petaluma.

It is the third body to be found in town since Aug. 16.

The first was found badly decomposed on that day near the end of McNear Peninsula. The person, an adult female, has yet to be identified, though police have said it is likely she was a transient.

Then, last Thursday, a dead man was found in Willow Brook Creek, his body also decomposed. A cause of death has not been determined, but again, police said he was likely homeless.

Wednesday, police received a call alerting them to a possible dead body under the D Street Bridge at 3:47 p.m.

Officers discovered the body of an adult man. Police said in a statement that they believed the body had been there since sometime Wednesday.

Police added that they believe the man's death may have been a suicide.

Detectives conducted a search of the area, which police say is frequented by transients.

The coroner's office will conduct an autopsy help identify the body and possibly determine a cause of death.

Police are asking anyone with information on the incident to call the Petaluma Police Department at 707-778-4372. Anyone wishing to call anonymously can do so at PPD Crime Tips at 707- 781-1200 or email ppdtips@ci.petaluma.ca.us.