Two men were injured and one man arrested after a collision on the A27 yesterday.
The road was closed when a lorry hit a slow-moving people carrier, turned over and went through the central reservation.
The 49-year-old male driver of the people carrier suffered suspected leg and chest injuries and was taken to the Royal Sussex County Hospital in Brighton for treatment.
The 79-year-old passenger of the car suffered serious head injuries and was flown to Southampton General Hospital.
The 44-year-old lorry driver was treated for minor injuries before being arrested for careless or dangerous driving.
He remains in custody this morning.