The incident began around 9:55 p.m. Friday when a call reported that a vehicle flashing its emergency lights had pulled to the right-hand shoulder of the highway, CHP Officer Shawn Chase said.
Arriving officers discovered a man suffering fatal gunshot wounds lying next to a white Ford Mustang Cobra on the highway shoulder, Chase said. The man was the vehicle's only occupant and died at the scene.
Brisbane police responded to investigate the shooting with assistance from other agencies, closing all southbound lanes.
One lane reopened around 3 a.m., and the remaining lanes cleared around 4:20 a.m., CHP Officer Aaron Quistad said.