The A27 is closed after a crash at lunchtime left two people with serious injuries.
The road closure has led to long delays for commuters returning home to Brighton and Hove and people heading out of the city to East Sussex.
Diversions have added to rush-hour congestion on the A259 between Brighton and Newhaven.
More than four hours after the pile up, Sussex Police said: “Police are continuing to respond to a multi-vehicle collision on the A27 just east of Beddingham Roundabout, near Lewes.
“Four vehicles – a Ford Transit, a delivery van and two cars – were involved in the incident, which occurred at around 12.24pm on Thursday 17 June.”
The delivery van was a DPD van.
Sussex Police added: “Two people have been taken to hospital – a man with life-changing injuries and a woman with life-threatening injuries. No other injuries were reported.
“The A27 will remain closed in both directions between Beddingham Roundabout and Polegate for some time, to enable investigations and recovery work to be completed. This includes debris and damage to the road surface.
“The A26 remains open.
“In the meantime, motorists are advised to use the diversions which are signposted.
“HGVs in particular are urged to follow these diversions and not seek alternative routes, as this has already caused some vehicles to become stuck in nearby country lanes.
“Police are urging anyone who saw what happened – or anyone with relevant dashcam footage – to email email@example.com quoting Operation Craven.
“We’d also like to thank the public for their patience and understanding.”
This morning a crash on the eastbound side of the A27 between the Devil’s Dyke roundabout and the A23 London Road also caused queues and delays.
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