Road users are being diverted after a major crash has occurred on the M11 between junction 7 and 8.
A multiple car crash, involving a horse box, a lorry and several other cars, has caused a complete closure of the northbound carriageway of the motorway.
Although the southbound carriageway remains fully open there are some delays being experienced.
Emergency services are currently on scene, and a police investigation is underway.
The motorway will reopen as soon as it is safe to do so but the closure is expected to last for several hours, through the evening rush hour and into this evening.
Current delays are at least 30 minutes.
Drivers, and in particular those wishing to travel to Stansted Airport, are advised to plan their journeys and allow extra time to travel.
Road users wishing to access Stansted and travelling on the M25 anticlockwise should consider taking the A12 to Chelmsford, then the A130 north to Braintree, and then the A120 westbound to Stansted.
Drivers travelling on the M25 clockwise should consider taking the A1(M) and then the A1 northbound up to St. Neots, then the A428 eastbound to Cambridge, where it meets the M11.
Traffic is being diverted locally at junction 7 on to the A414 northbound to Harlow and then westbound to Hertford.
Join the A10 northbound to Puckeridge and then take the A120 eastbound to junction 8 of the M11.