The incident happened on the stretch of road between the B661 Perry Road, in Buckden and Diddington at around 3.10pm. A spokesman for Cambridgeshire police said: We called at 3:10pm to the A1 at Diddington to reports of a two vehicle collision. As a result of the incident it appears that one female injured. Crews from Cambridgeshire Fire and Rescue Service and the East of England Ambulance Service are also at the scene. Following the accident the A1 Great North Road in Buckden has been closed as a result and there is queuing traffic between Buckden roundabout and the Southhoe turn off. There is also congestion at the Offord turn off. Drivers are being advised to use alternative routes and avoid the area if possible.