The A47 was closed after a serious crash.
Emergency services were called to the crash near Wisbech Bypass on Sunday morning.
Drivers were being asked to avoid the area while police and paramedics attended the scene.
A spokesman for Fenland Police said: "Please avoid A47 Wisbech Bypass. We are currently dealing with a road traffic collision.
"The road is due to be closed for the foreseeable future."
However the force has since confirmed the road has reopened.
The number of vehicles involved and the extent of any injuries is not yet clear.
According to the AA Traffic Map there were long delays in the area.
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