Berkeley police are investigating a fatal vehicle collision involving a pedestrian and a suspected DUI driver in the parking lot at Aquatic Park, according to the police department. The collision occurred at about 4:35 a.m. Wednesday in a roundabout at the park, police said. The driver remained at the scene and was arrested on suspicion of driving under the influence. One witness at the scene said he saw a man in a sleeping bag who had been run over by a car in the parking lot, and he and the car’s driver tried to push the car off the victim. The Berkeley Fire Department also responded, and video footage shows first responders attending to the victim, who was pronounced dead at the scene. No other details were immediately available.