A car fire on the A1(M) is currently causing severe delays between Welwyn Garden City and Hatfield.
The blaze is on the southbound carriageway between Junction 4 for Tesco and Junction 3 for the university.
There is congestion in both directions of the motorway, which is particularly bad southbound, and motorists are being advised to avoid the route while emergency services deal with the fire.
More to follow.
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