The crash was reported just after 6 a.m. when a red pickup truck apparently drove the wrong way up a westbound Highway 80 off-ramp at Ninth Street and crashed into another vehicle, CHP Officer A. Paulson said.
A passerby driving a gray Mazda stopped to assist both drivers, attending to the man driving the pickup truck first, Paulson said.
When the good Samaritan went over to assist the second driver, the driver of the pickup truck hopped into the good Samaritan's vehicle and fled the scene, she said.
Officers recovered the stolen vehicle at 11th and Howard streets at 8:23 a.m., but the suspect was nowhere to be found.
The second driver involved in the crash was taken to a local hospital with minor injuries, Paulson said.
Paulson said investigators will attempt to recover fingerprints from both the pickup truck and gray Mazda to identify the suspect.
Traffic was snarled on the Bay Bridge during the morning commute while the crash blocked the off-ramp. Paulson said the off-ramp reopened at about 9:45 a.m. after the last officers had left the scene.