Police are appealing for witnesses after two BMW cars were in collision on the A27 Lewes Road, Polegate, on Saturday (28 June).
Emergency services were called at 7.47am near the junction of Gainsborough Lane where a black BMW 520 car travelling east was in collision with another black BMW 320 travelling west.
The impact caused the BMW 520 to burst into flames and the driver, a 26-year-old man from London, was pulled from the car.
He was flown by air ambulance to St George’s Hospital, Tooting, with life threatening injuries and is in a critical condition.
The driver of the BMW 320, a 45-year-old man from Eastbourne, suffered minor injuries and his passenger, a man aged 39 also from Eastbourne, suffered a serious back injury.
Both were taken to Royal Sussex County Hospital, Brighton.
The driver was released from hospital but his passenger remains there in a stable condition.
The road was closed for vehicle recovery and forensic collision investigation to take place and re-opened at 1.15pm.
Anyone who witnessed the collision is asked to call police on 101 or email firstname.lastname@example.org quoting Operation Foundation.