A Tesla driver told police his car was in “full self-driving” mode when it suddenly braked, leading to an eight-car pileup on the San Francisco Bay Bridge last month, according to a California Highway Patrol traffic crash report. The incident on Thanksgiving Day left nine people needing medical treatment for minor injuries, including one juvenile who was taken to hospital. The lunchtime crash unfolded when the Tesla Model S moved into the far lefthand lane and braked, slashing the vehicle’s speed from around 55 mph to 20 mph, the report said, and triggering a cascade of crashes. The report, dated Dec. 7, said police could not confirm if the car was in “full self-driving mode” at the time of the incident. Mere hours before the crash, Tesla boss Elon Musk announced that the software was available to anyone in North America who requested it. It had previously only been offered to drivers who scored well on Tesla’s safety rankings.