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.
More top news
A coroner has ruled Addenbrooke's hospital in Cambridgeshire is not guilty of gross negligence following the death of a Norfolk grandfather
The employee was sorting through rubbish at waste company Amey's Waterbeach facility.
Ice is expected to form on some surfaces from late Tuesday afternoon and last overnight into Wednesday morning.