Driver are being warned of long delays on the M25 at Kent following a crash involving a lorry and a car.
Police were called at 3:46am to a report of a road traffic collision on the clockwise M25 at junction 2. The car and lorry collided then the car hit the central reservation.
One man in the car has suffered serious injuries. Three further people have suffered minor injuries. All have been taken to hospital for treatment.
The clockwise carriageway remains closed while officers continue their enquiries.