Three men, including a 33-year-old from Southwater, have been taken to hospital after the collision on the A24 this morning (Tuesday March 10).
Sussex Police confirmed the A24 northbound near Southwater will be closed for the rest of today following the three-vehicle collision at 7.25am.
Police said a Ford Focus was involved in a head-on collision with a Vauxhall Combo van. A Renault van then collided with the rear of the Vauxhall.
The road needs to be resurfaced, police added.
The driver of the Ford, a 33-year-old man from Southwater, was taken to Worthing Hospital with slight injuries.
The driver of the Vauxhall, a man aged 53 from Sompting, was flown by air ambulance to the Royal Sussex County Hospital, Brighton, with a serious chest injury. He is in a stable condition.
A 26-year-old man from Worthing who was driving the Renault was taken to Worthing Hospital with slight injuries.
Sergeant Rob Baldwin said: “The A24 northbound will be closed all day while the road surface is repaired. We are asking motorists to follow the diversions or avoid the area if possible.
“We are appealing for witnesses to the collision to come forward.”
Anyone with information can contact police on email@example.com quoting Operation Usher.