Traffic is severe on the A12 southbound following a multi-vehicle crash which created more than six miles of tailbacks.
The crash happened shortly before 5pm between junction 19 for Boreham and junction 20 for Hatfield Peverel.
The southbound carriageway was closed completely by police for more than an hour, with traffic grid-locked as far as Kelvedon as a result.
The extent of any injuries is not yet known.
Highways England has warned drivers to expect an extra 45 to 60 minutes on top of their usual journey times.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here