There are a major delays on the M11 in Essex after a multi-vehicle crash.
The accident happened on the northbound carriageway between junction 7 for Harlow and Junction 8 for Bishop's Stortford.
Police and the air ambulance have been called to the scene and traffic is being held while they deal with the scene.
Highways England say the congestion is likely to remain until mid afternoon.
The southbound carriageway was also closed so the air ambulance could land.
There are fears people trapped in the traffic jam will miss flights at Stansted and there have been reports of people leaving cars and walking along the carriageway to get to the airport.
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