Sgt Paul Lunt said: “The victims were just walking on the pavement when a car mounted the pavement and collided with them, causing serious injuries before driving off, leaving the girls injured by the road.”
The officer urged anyone who witnessed the incident, or who may have CCTV, dashcam or doorbell footage of a silver VW Golf driving in the area at the time to contact the force.
“After the collision, the VW Golf had a smashed windscreen, so should be quite distinctive,” he added.