A major emergency operation went into action last night after a collision involving a double decker bus and a car on the A47 near Wisbech.
No details of casualties have yet been released but local residents say an air ambulance was called together with police, and fire crews.
Cambridgeshire Police said the road is now re-opened.
The collision happened between the A141 near Guyhirn and the B198 near South Brink and has led to the closure of the A47.
Lorry drivers caught up in queues were seen reversing back to the Guyhirn roundabout to find alternative routes.
Highways England reported it as a “serious road traffic collision.
“Cambridgeshire Police and ambulance services are at the scene,” said a Highways England official.
“Road users are advised to expect delays on the approach to the closures and allow extra time for their journeys.”
Cambridgeshire Fire and Rescue said crews from March and Wisbech are working with police and ambulance colleagues at the scene.
“The road is closed and will be for some time so please avoid the area tonight,” said a statement from Cambs fire and rescue.
An eye witness confirmed “the crash was between a car and a bus”.
One nearby resident posted to Facebook: “The lorries are reversing back to the roundabout so I think it's going to be a long closure.”
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