Sgt. Matthew Koch said emergency workers were called to the 2600 block of Somersville Road just after 7:30 p.m. for reports of a vehicle collision involving a pedestrian.
When first responders arrived they found the child unresponsive in the parking lot. She was rushed to a local hospital, where she was pronounced dead.
The driver stayed at the scene and was cooperating with police as they investigated, Koch said. Drugs and alcohol didn't appear to be a factor in the collision, according to Koch.
He didn't say if the driver will face charges.
Anyone with information about the incident is asked to call (925) 779-6900 extension 84265, or email ejohnsenci.antioch.ca.us.