Drivers are experiencing long delays after a crash on the M4.
The motorway is closed eastbound between junctions 10 and eight.
One lane is closed westbound with traffic moving very slowly.
Police and paramedics are at the scene.
UPDATE - 6pm: The eastbound carriageway is not expected to re-open until 8.30pm.
There are delays of about 50 minutes westbound between junctions seven and eight.
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