There are severe delays on the M4 westbound between junctions 8/9 to 10 due to an accident involving an overturned van.
The Highways Agency is reporting the westbound entry at junction 8 is closed and the road is not expected to re-open until 3.45pm.
The Royal Berkshire Fire and Rescue Service (RBFRS) has tweeted that crews from Maidenhead and Slough have freed a person from an overturned van between junctions 8/9 and 10.
It warns of heavy congestion as a result of the accident.
The Highways Agency is now reporting minor delays heading westbound, with one lane remaining closed following the incident.
Normal traffic conditions are expected from 6pm.
The van driver involved in the crash has been taken to Royal Berkshire Hospital, in Reading.
His injuries are not thought to be life-threatening.
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