A FedEx truck driver who struck and seriously injured a California Highway Patrol officer in Sacramento has been arrested on suspicion of driving under the influence.

KCRA-TV reports 41-year-old Gregory Anthony Ramirez was booked for investigation of felony DUI and possession of a controlled substance following Saturday's accident.

The CHP said Officer Vincent Smith, an 18-year veteran of the agency, remained hospitalized Sunday.

Smith was trying to move cars from State Route 50 after they collided in a hit-and-run crash when he got hit. The back of his patrol car was mangled after being hit by the truck. Authorities said Smith was on foot at the time. It's not clear whether the truck hit the officer or whether it struck the patrol car, causing it to hit the officer.