The A259 is currently closed due to a four-car collision outside Eastbourne, according to traffic reports.
The accident reportedly happened on East Dean Road between Gilberts Drive and Warren Hill, and was first reported at 6.45pm. This section of road has been closed, traffic reports say.
Traffic reports say that vehicles are queueing in both directions along this stretch, affecting traffic between Seaford and Eastbourne.
A detour is in operation via Gilberts Drive, Burling Gap Road, and Beachy Head Road.
A spokesman for East Sussex Fire and Rescue Service said they were called to the scene at 7.08pm, made sure the scene was secured and left at 7.22pm, leaving the scene in the hands of the police.
The condition of the drivers and passengers is currently unknown.
Sussex Police has been approached for more details.