A 27-year-old man from Portslade has died after his car crashed into a tree just outside Hassocks.
The man was flown to hospital in London for treatment but could not be saved.
A helicopter took him to the Royal London Hospital after the crash which happened at about 1pm on Friday (26 August).
The man’s blue BMW left the road on the A273 Brighton Road in Clayton, just south of Hassocks.
No other vehicle is believed to have been involved.
Anyone who saw the accident or who saw the blue BMW shortly before it crashed is asked to contact Sussex Police on 0845 6070999.