Drivers from Brighton and Hove were being urged to avoid a stretch of the A27 for several hours after a pedestrian was hit by car this morning (Thursday 9 February).
A 59-year-old man from Sompting died at the scene of the collision, near Lancing, despite attempts by paramedics to save him.
The road was closed shortly after the crash, which happened just after 6am, and reopened at about 11am, Sussex Police said, adding: “The Kent, Surrey and Sussex air ambulance flew to the scene.”
The force said: “The driver of a black BMW, a 58-year-old man from Climping, suffered minor injuries and was taken to hospital. He was later arrested on suspicion of causing death by careless driving and currently remains in police custody.”
The collision happened about a third of a mile east of the Lancing Manor roundabout on the A27 Old Shoreham Road – between Lancing and Shoreham.
Sussex Police said: “Heavy congestion ensued.”
Traffic queued back to the Southwick Tunnel at one point with thousands of drivers affected on their way to or from Brighton and Hove.
Sergeant Alan Spicer, from the Sussex Police Serious Collision Investigation Team, said: “We are appealing for anyone who was on that stretch of the A27 at around 6am and who saw what happened.
“Witnesses can email firstname.lastname@example.org or call 101 quoting Operation Anwick.”