Petaluma Police are looking for witnesses to a hit-a-run collision involving a pedestrian. On Wednesday evening, a man was crossing Sonoma Mountain Parkway just north of East Washington Street when he was hit by a Scion in the slow lane. The Scion was then rear-ended by a black Mitsubishi. The victim later reported that he was hit by a third vehicle that ran over his legs. He remains hospitalized in stable condition. Police are seeking information regarding that third vehicle involved which drove away from the scene.