Two people have been injured following a two-vehicle collision on the A1.
There are long delays northbound between Borehamwood and the M25 after the crash which happened at 2.20pm.
Two lanes out of three are blocked which has led to long tailbacks.
Paramedics are at the scene treating two people.
The crash site is just past the Holmshill Lane junction. Delays stretch all the way back to Stirling Corner.
Queues still remain on the M25 clockwise between j23 and j24 due to emergency repairs.
Meanwhile, delays continue in Elstree due to emergency sewer works. Work is expected to be completed by April 2.
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