Police say the 35-year-old rapper was arrested early Sunday after being pulled over for a red light violation. Officer Karen Smith says marijuana was found in the vehicle.
The rapper's real name is Warren Griffin III. Both he and the driver were booked on suspicion of possessing a controlled substance.
They each posted $20,000 bail and were released. A phone message left for Griffin's agent, Al Hassas, was not immediately returned Sunday.
Warren G was nominated for a Grammy in 1995. He was arrested in 1996 for carrying a loaded assault weapon in his truck.