All lanes have reopened westbound between junctions 6 and 8/9 of the M4 following a collision this morning.
The Thames Valley Police Roads Policing Twitter account said at 11.22am that two vehicles had collided in the area and the carriageway was briefly closed.
The Highways England account said the closure was due to a 'heavy vehicle fire' and police were working to release trapped traffic.
All lanes reopened shortly before 1pm.
A van fire forced the partial closure of the M4 this morning.
Fire crews from Slough, Windsor and Langley were sent to the westbound section of the motorway between junctions six and seven at about 11.30am.
Firefighters spent about an hour bringing the blaze under control following a collision between a white Renault van and a Volkswagen hatchback.
The driver of the car, a woman, was treated at the scene but no one else is believed to have been injured.
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