Delays are affecting traffic travelling westbound on the M4 between junctions 7 and 8/9 near Maidenhead.
A police spokeswoman said there was a collision between vehicles, but no one was hurt.
The damaged vehicles have been moved to the hard shoulder but traffic is still moving slowly.
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The victim of an assault in Cippenham was flown to hospital by air ambulance this afternoon.
A rapid response vehicle, an ambulance officer, an air ambulance and an ambulance crew were all called to an address in Earls Lane at 2.10pm.