Drivers are facing serious delays on the M25 this morning due to emergency repairs.
One lane is closed in both directions near junction 25 for Enfield and Waltham Cross after a crash overnight.
Highways England says the lane closures are in place just east of the Holmesdale Tunnel.
The agency tweeted: "If you're travelling on the #M25 this morning towards J25 for #Enfield, please allow extra time for your journey as lane 4 is closed both sides on the eastern side of #HolmesdaleTunnel following an overnight traffic collision compromising the central reservation barrier."
As a result of the lanes being closed, there are significant delays on the motorway, particularly for motorists travelling anticlockwise from Essex.
As of 8.30am, there are queues from junction 27 for the M11 all the way to near junction 25, with traffic heaviest between junctions 27 and 26.
Delays were at least 30 minutes but now believed to be much longer.
The problems on the M25 are also impacting local roads nearby, such as in Epping Forest and on the A10 on the Enfield/Hertfordshire border.
The M25 clockwise carriageway is faring better than anti-clockwise with slow traffic approaching junction 25.
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