Emergency services were called to a serious collision in Bexhill on Saturday afternoon (February 1).
Police, ambulances, and collision investigation teams were called to King Offa Way at about 4pm.
The driver of a black saloon car suffered serious injuries in the incident, police said.
One car was involved and the road was closed both ways for several hours as the scene was investigated.
Police are appealing for any witnesses to come forward using the reference Operation Dalewood.