Police are appealing for witnesses after a car left the carriageway in Pease Pottage this morning, leaving three people injured.
Emergency services arrived on the scene at the A23 at Pease Pottage, near Crawley, at 6.16am.
A car had been travelling northbound overtaking other traffic when it left the carriageway and rolled over several times, before coming to a rest on an embankment, according to police.
Three people were inside the car, a black Volkswagen Polo, and all sustained injuries, police said.
An 18-year-old woman from Crawley, who was a rear seat passenger, was taken to the Royal Sussex County Hospital, Brighton, by ambulance for treatment, according to police.
An 18-year-old man from Redhill, Surrey, has been arrested on suspicion of drink-driving, confirmed police.
The nearside lane of the three-lane carriageway was closed and a temporary speed limit imposed until 7.40am while the incident was dealt with.
Anyone who saw what happened or noticed the black VW being driven shortly beforehand is asked to email email@example.com or phone 101, quoting serial 217 of 11/07.