Police are appealing for witnesses after a car ran into a pony carrying a child and then drove off.
The nine-year-old victim was riding his pony in Loxwood Road, Rudgwick, when the animal was struck from behind by a silver car.
The boy was knocked into a hedge to his left and the pony ran off, dragging with it the boy’s mother who had been holding the reins and walking in front.
The driver did not stop at the scene.
The incident happened shortly after 10am as the family were travelling south west along the road, towards The Fox Inn at Tismans Common.
Police are carrying out forensic tests on a wing mirror knocked off in the impact to try to link it to the vehicle involved and its driver.
The mother suffered a hand injury and had to go to hospital for treatment. The boy suffered cuts and bruises.
A vet visited to check the pony for injuries. It had suffered cuts and bruises.
PC Karen Whitehouse, of Sussex Police road policing unit, said: “The boy was fortunate to have fallen into the hedge and not into the road where he could have suffered more serious injuries.
“It is clear from the debris left at the scene that the driver must have known that they had hit the pony but did not bother to check on the animal, the boy or his mother.
“We have seized a silver Peugeot that we are examining to try to confirm if it is the vehicle involved.
“If anyone saw the car being driven in the moments before or after the incident or who knows anything about what happened I would urge them to contact us.”
Anyone with any information should call 101 quoting serial 387 or email firstname.lastname@example.org