The two cars involved are a Ford Fiesta in red, and a Volvo S60 in silver.
The Volvo initially caught fire and both Ambulance and Fire Rescue services attended the scene before order could be restored.
One driver has been taken to hospital with a back injury.
The Highways agency have attended to deal with the issue of diesel on the road.
The route has since been reopened.
PC Jamie Brown, attending has said: “It was quite a busy scene, and although one party has been taken to hospital it is good news that both drivers were walking and talking.
“Ambulance, Police and Fire Rescue have made a combined effort working together to get the road back open.
“We’re grateful to everyone for their patience.”
Press Release from Ely Police