A man assaulted an MBTA bus driver over the weekend, causing the bus to veer off the road and smash into a parked car, MBTA Transit Police said. The incident occurred on Broadway in Chelsea at about 9:28 p.m. Sunday, police said. Surveillance video shows the man becoming upset at the driver and getting close to the driver before he pushes him away. The bus then veers to the right and crashes into a parked car. Transit Police asked anyone with information regarding the suspect to call them at 617-222-1050.