Police are appealing for witnesses after a car left the North Bank road and entered the water.
The driver, a 50-year-old man from Northamptonshire, was pronounced dead at the scene yesterday (Monday) after the Skoda Octavia he had been in was recovered from River Nene which runs alongside the road in Whittlesey.
Police and emergency services were called shortly after 2.30pm to reports that a vehicle had been spotted partially submerged in the water.
The road remains closed this morning while further inspections are carried out. It is thought the car may have entered the water as early as November 26.
PC Tim Kirkby, investigating, said: “I would appeal to anyone who saw the vehicle enter the water or saw it being driven along that stretch of road between Tuesday (November 26) and 2.30pm yesterday.”
Anyone with any information should call the Roads Policing Unit on 101.