The crash involved a sheriff's patrol unit and happened just before 10 p.m. near the area of Brown and Oakwood streets, according to a CHP traffic incident log.
Two people in the civilian vehicle were reportedly trapped and had to be cut free by firefighters. They were rushed to a hospital with severe injuries, and their white vehicle was left flipped on its side and severely crushed.
The deputy involved in the crash was also taken to a hospital in unknown condition. Footage from the scene showed the patrol vehicle with heavy front-end damage on the side of the road.
It's unclear what caused the crash.