Police have confirmed it was called to reports of a collision between a car and a pedestrian earlier today on Lower Bognor Road, in Lagness, near Chichester.
A spokesman said the road is currently still closed in both directions and that the pedestrian, believed to be in his late teens, was air lifted to Southampton General Hospital following the incident around 3.10pm this afternoon.
Emergency services are still on scene and there are no further details at this stage, police confirmed.
This story will be updated accordingly.
If you witnessed the collision please report online or call 101 quoting Operation Bargate.