The A12 in Essex has partially reopened after the air ambulance was called to a serious crash outside Chelmsford.

The crash happened between junctions 17 and 18 on the northbound carriageway shortly after 1pm, Essex Police said on Twitter.

According to the AA traffic map, lengthy queues formed in both directions on the road.

Police warned the road was likely to remain closed for some time.

The A12 southbound between J18 and J17 has reopened but the northbound carriageway remains closed.

The southbound carriageway also shut to allow for the air ambulance to land.

The closure means the road connection Suffolk and London were blocked, with drivers urged to find alternative routes.

For up-to-date information about the county's roads, visit our LIVE traffic map.

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