RICHMOND ? A man suspected of gunning down his girlfriend and another person at the entrance to the Richmond-San Rafael Bridge was arrested after an overnight manhunt, police said Wednesday.

California Highway Patrol officers arrested Nathaniel Burris, 46, around 3:15 a.m. Wednesday in Placer County, about 120 miles northeast of the shooting at the toll plaza. Authorities said Burris was sleeping in an airport shuttle van, but drove off after CHP officers approached and surrendered after a short chase.

Burris was booked into Placer County Jail on two counts of murder.

He's suspected of being the driver who opened fire with a shotgun around 6 p.m. Tuesday, killing his girlfriend, Deborah Ross, who was a 51-year-old California Department of Transportation toll booth collector, and 58-year-old Ersie Charles Everett, who was sitting in his truck in the toll plaza parking lot.

Ross and Burris shared a house in Richmond, and neighbors said the two had been having financial problems.

Everett also was a state transportation employee and had driven Ross to work Tuesday, authorities said. Richmond police said they're looking into the relationship between the victims.

Witnesses said a man used the butt of a shotgun to shatter the window of the No. 3 toll booth, then fired at least three times before fleeing in the van. Officers found Ross' body inside the booth. Patrol Sgt. Trent Cross described the scene as "horrific."