A teenage Uckfield driver suffered whiplash injuries after her car was in collision with a Land Rover on Sunday afternoon.
Police said at about 5.20pm an old style light green coloured Land Rover pulled out from a lay-by on the A22 between the Bell Farm junction at Uckfield and the Little Horsted roundabout.
In doing so it went into the path of a white Renault Clio being driven by a 17-year old Uckfield girl.
The Clio had to take evasive action and hit near side crash barriers.
The Land Rover failed to stop and continued south on the A22.
The Clio driver was treated at Eastbourne District General Hospital and her car was seriously damaged.
PC Colin Moon said: “Any witnesses are asked to call us on 101 quoting Serial 0970 28/04.”