A teenager got out of a car in Saltdean and was then run over by the driver.
The 18-year-old woman suffered a serious leg injury as a result and was taken to the Royal Sussex County Hospital in Brighton for treatment.
Sussex Police said that the car was abandoned in a car park near by.
A 22-year-old man from Telscombe Cliffs was arrested at the scene on suspicion of causing grievous bodily harm.
A detective has issued an appeal for witnesses to the incident which happened just before 11.15am yesterday (Friday 31 August) on the A259 Marine Drive at the junction with Saltdean Park Road.
The teenager was hit by a black Mazda 3 saloon.
Sussex Police said that it was believed that the car stopped in Marine Drive, the woman got out and was then hit as she crossed the road.
Detective Inspector Miles Ockwell said: “The victim and the driver know each other so that this does not appear to be a random incident.
“The woman has received a serious injury and, although we have yet to establish the full circumstances, we are clearly considering that the collision may have been deliberate.”
Anyone with information is asked to call Sussex Police on 101 or the independent charity Crimestoppers anonymously on 0800 555111.
