A car is on fire on the M1 Credit: Jack Fenton
All lanes are now open following a car fire.
The M1 was blocked northbound between j4 and j5 for Watford.
Emergency services were called to the scene but Highways England have reported all lanes have opened.
Traffic was brought to a standstill for more than a half-an-hour after the black car burst into flames on the hard shoulder during rush hour.
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