FGW have put a coach replacement service in place.
A spokesman said a vehicle had hit a bridge in Maidenhead but could not confirm details.
Trains between Marlow and Bourne End are running normally.
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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.