A tractor and a lorry crashed at a notorious accident spot near Ely.
Emergency services, including the East Anglian Air Ambulance, East of England Ambulance Service, police and fire service, were called to the collision on the A142 at Witcham Toll.
The accident happened at around 7am on Saturday.
Firefighters from Ely and Sutton had to cut one casualty free from their vehicle using specialist cutting equipment.
The condition of both the lorry driver and the tractor driver is not known.
The road was closed for more than two hours, causing lengthy delays for motorists.
Residents have been calling for safety improvements at Witcham Toll for some time.
But Cambridgeshire County Council says that work carried out in 2002 has reduced the number of accidents there.
The council says it is looking at what further improvements could be made.