Police are appealing for witnesses and dash-cam footage following a serious collision near Cowfold.
Officers, ambulance and fire crews were called to the A272 at 8.55am on Tuesday (22 September) to a crash involving a white van and a sewerage lorry.
The van driver – a 22-year-old man – was air-lifted to hospital with serious injuries.
The lorry driver was taken to hospital with minor injuries.
Road closures remain in place and further disruption can be expected this afternoon.
Sergeant Chris Ambrose said: “We are investigating the circumstances of this collision and are keen to hear from anyone who witnessed what happened or may have dash-cam footage of either of the vehicles.
“If you have any information you believe may be able to assist with our enquiries, please report online or call 101 quoting Operation Stirling.”