There are serious delays on the M25 near Orpington and Swanley after a car pulling a caravan overturned.

The main carriageway is blocked between junctions four and three anticlockwise following the incident.

The Highways Agency has said lane one is now running past the scene but two and three remain closed for a clean up and recovery operation.

Delays are reportedly pushing traffic back as far as junction five. 

More to come.