THE M11 has been closed in both directions due to an overturned lorry which has spilled chemicals across the carriageway.
The emergency services are at the scene where the lorries crashed at about 5pm on the northbound carriageway between junctions 7-8 Harlow to Bishops Stortford/Stansted Airport.
The motorway is closed in both directions and motorists are urged to find alternative routes and there is already heavy traffic congestion.
No other vehicles are believed to have been involved in the incident.
It is not known how long the road will be closed for.
Northbound traffic is advised to follow hollow diamond symbol on diversion signs, which will direct traffic to leave the M11 at Junction 7 and take A414 through Harlow and continue west to A10, then take A10 north to Puckeridge and join A120 east to junction 8 of the M11.
Southbound traffic should follow the Hollow square diversion signs to follow the same route in reverse.
The Fire Service will be dealing with the spillage in liaison with the Environment Agency and Ambulance service are treating the driver of the tanker, who has received cuts and bruises but is not believed to be seriously injured.
Motorist caught up in the closure are advised to stay with their vehicles and wait for instructions.
A Essex County Fire and Rescue spokesman said: "The chemicals have been identified as melamine formaldehyde resin and phosphoric acid. Crews are standing by awating scientific advice."