Police are seeking witnesses after a blue BMW crashed into a railway barrier on the A259 at Rustington
The male driver was taken to Royal Sussex County Hospital in Brighton by air ambulance, suffering serious injuries. No other vehicles were involved.
The road has been closed in both directions as emergency services remain at the scene, and motorists are advised to seek alternative routes in the meantime.
Anyone who saw what happened or who witnessed the vehicle being driven in the area immediately before the crash – or anyone with dash cam or any other footage – is asked to come forward.
You can email [email protected] quoting Operation Kelso.