Police are investigating a video which shows an officer repeatedly striking a motorist with a baton while another officer tries to hold the suspect down. 43-year old Darren Johnson was pulled over for traffic code violations at about 10:30 p.m. Monday in the 200 block of West Highland Ave, according to San Bernardino Police Lt. Dan Keil. Officers say Johnson became increasingly agitated and aggressive and struck one of the officers. Johnson was booked into West Valley Detention Center in Rancho Cucamonga on suspicion of possession of cocaine, transportation of cocaine and assault on a peace officer, Keil said. The video, filmed by 38-year-old Brandon Piddington, appears to show one officer holding a man down on the ground and another striking the man in the legs about nine times with a baton.