A teenage girl spotted a naked homeless man masturbating on a rock in the middle of Santa Rosa Creek downtown Monday.

The 14-year-old reported it to police around 5:45 p.m. as she walked along the Prince Memorial Greenway near A Street, according to Santa Rosa police.

Police arrived moments later to find Cosbie Marable, 29, “sitting on a rock in the middle of the creek just for the whole world to see,” Sgt. Kyle Philp said.

Marable, who was wearing “not a sitch” of clothing, was arrested on suspicion of indecent exposure, committing a lewd act in public and violation of probation, and booked into Sonoma County Jail.

You can reach Staff Writer Kevin McCallum at 707-521-5207 or kevin.mccallum@pressdemocrat.com. On Twitter @srcitybeat.