UPDATE Thursday, October 13, 8.57am:
The M4 has now reopened.
The westbound carriageway of the M4 looks set to remain closed until the early hours of the morning after a lorry overturned earlier this afternoon.
Police estimate the carriageway is unlikely to reopen for at least 10 hours after a man was freed from the lorry and taken to the John Radcliffe Hospital in Oxford by air ambulance.
The incident took place shortly after 12.50pm on the westbound carriageway between junctions J8/9 and J10.
The eastbound carriageway was also briefly closed to allow the air ambulance to land.
A spokesman for South Central Ambulance Service said an ambulance, a paramedic team and an air ambulance were called to the scene and assisted a man trapped inside the overturned lorry.
A spokesman from the Royal Berkshire Fire and Rescue Service said: “We were called to the incident at 12.52pm.
"We sent one pump from Maidenhead, Windsor, Slough and a heavy rescue unit."
Westbound traffic is being diverted off the M4 at junction J8/9 and taking a diversion route via the A404(M) and A4 towards Reading.
We are dealing with a serious collision m4 jct 8/9 to 10. The clear up is expected to take several hours. pic.twitter.com/AfF8g4oyRx— TVP Roads Policing (@tvprp) October 12, 2016
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