The emergency services are currently at the scene of a serious crash on the A47 near Wisbech.
Drivers say a lane has been closed westbound on the dual carriageway between Walton Highway and the Worzals roundabout.
It is not known exactly when the crash happened. Delays are expected for some time.
One driver who recently passed the incident said it looked as though a vehicle had gone into the back of a lorry in a layby.
He said six police cars, two ambulances and three fire engines are in attendance.
The police, ambulance service and the fire service have all been approached for comment.
Story will be updated as more information arrives...
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