Police are appealing for witnesses to a serious collision on the A27 at Hammerpot near Arundel.
The collision occurred westbound at 6.50am on Saturday (20 August) and involved two vehicles a black Ford Kuga and a white Renault Clio.
Five people were injured, including a passenger in the Ford Kuga who sustained serious injuries. They were all taken to hospital.
The road remains closed for investigation and vehicle recovery and diversions are in place.
Anyone who saw the collision happen or has relevant dashcam footage of the incident is asked to email collision.appeal@sussex.police.uk quoting Operation Risley.