Friday evening rush hour is likely to be even more of a headache for commuters as two incidents have led to delays on the M1 in both directions.
Emergency services have been at the scene of a suspected lorry fire on the southbound carriageway between Junction 9 for Redbourn and Junction 8 for Hemel Hempstead for more than two hours.
It is thought the white heavy goods vehicle had smoke pouring out of the back and was spilling oil across lanes 1 and 2 of the motorway.
Police arrived at the scene shortly after 1.30pm and called the fire brigade for assistance, though when they reached the incident it was discovered there was no fire situation.
Lanes 1 and 2 were closed due to oil on the road surface, and the affected vehicle was recovered at 2.15pm.
Since then, the Highways Agency have been clearing the road surface and all but lane 1 and the hard shoulder have been reopened.
There remain heavy delays as far back as Junction 10 for Luton.
An earlier accident on the M1 northbound in Bedfordshire has also caused delays between Junctions 13 and 14. An ambulance, paramedic officer and an air ambulance from Magpas attended where a man in his 30s was trapped in a lorry by his legs and was receiving treatment.
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