DELAYS are expected following a ‘serious collision’ involving an overturned vehicle on a major road.

There are delays of about 15 minutes on the A12 northbound as traffic is building following a collision.

The northbound carriageway is closed between the Danbury and Boreham Interchange, junction 18 and 19, whilst all emergency services are at the scene.

Drivers have been advised to divert the incident at junction 15 and re-join at A12 at junction 19.

The carriageway is expected to be closed for a number of hours whilst the incident is investigated, vehicles are recovered and the scene is cleared.

A spokesman for National Highways said: “All lanes are closed following an earlier accident involving an overturned vehicle.

“The A12 near Chelmsford is closed northbound between J18 and J19 following a serious collision.

“All emergency services are at the location with Essex Police managing the incident.

“It is expected the carriageway will be closed for a number of hours whilst police complete collision investigation, recovery of the vehicles and carriageway clear up.

“The below diversion route is from J15 to J19.

“Road users are advised to follow the below diversion which is not symbol led.

“Exit at J15 Webb's Farm and follow the A414 to the roundabout with the A1114.

“Take the second exit on to the A1114.

“At the next roundabout take the first exit on to the A1016.

“Continue on the A1016 to the roundabout with the A130.

“Take the second exit from the roundabout and follow the A130 to re-join the A12 at J19.

“If this closure impacts on your planned route, please allow extra journey time. Plan ahead, you may wish to re-route or even delay your journey.

“Further information is available from National Highways by visiting our  www.trafficengland.com website and travel apps, or via our regional twitter feed.

“Our 24/7 contact centre team is also available to provide up to the minute information on 0300 123 5000.”

Essex Police and the East of England Ambulance service have been approached for comment and more information.