A three car collision shut the M25 by Potters Bar.
Anti-clockwise traffic was stopped between junction 25 by Waltham Cross and junction 24 for Potters Bar, to allow the emergency services to clear the incident.
The East of England Ambulance Service are currently on the scene, and only one lane is still closed.
There are about 30 minute queues on the approach to the incident.
Travelling conditions are expected to return to normal by 10.30pm.
For more information, visit www.trafficengland.com/
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 The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.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