The A605 at Ralph Butcher Causeway is currently closed because of a lorry fire.
Police and fire crews are currently at the scene.
A post on the Policing Fenland page on Facebook has warned drivers the road will be closed for the "foreseeable future".
Motorists are being advised to use an alternative route.
It said: "A605 closed at the Ralph Butchers causeway towards Whittlesey, for the foreseeable future.
"Please find an alternative route."
It is not yet known if there are any injuries.
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