The ambulance service says it is treating several people involved in the crash near Waltham Abbey.
A number of people have been injured in a crash involving multiple vehicles on the M25.
Essex Police said the crash between a lorry, a minibus and a car happened between the junctions for Waltham Abbey and the M11 at about 18:15 BST.
The motorway remains closed anti-clockwise between junctions 26 and 27 with emergency services at the scene.
East of England Ambulance Service said it was treating a number of people involved.
Police said the road would remain closed for hours.
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