A four-vehicle collision on the M1 between St Albans and Hemel Hempstead this evening has caused hour-long delays.
Three of the four lanes are currently closed following the collision northbound between Junction 8 for St Albans and Junction 9 for Hemel Hempstead.
Highways England said that the fire service has helped move the vehicles to the hard shoulder, but traffic is tailing back to Junction 21 of the M25.
It is currently unclear if anyone was injured.
Another crash on the M25 near Potters Bar has caused further congestion on the clockwise carriageway.
Motorists are being advised to avoid the routes where possible.
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