The A12 has been closed after a car overturned on the southbound carriageway.
The accident happened at around 4.30pm at junction 19 with the A138 with traffic is slow moving and backed up to junction 20 at Hatfield Peverel.
Emergency services are at the scene of a collision that involved a green Daimler and a silver Mercedes.
Police are advising motorists that the road has been closed at the Boreham junction whilst the vehicles are recovered. Motorists are being diverted and the incident is on-going.
