Officers would like to speak to anyone who may have witnessed the collision or saw either vehicle beforehand.
Officers are appealing for witnesses after a driver was seriously injured in a collision in Anstey on Friday (10 May).
The collision involved two vehicles, a blue Mini One and a silver VW Polo, in Anstey Lane, on the roundabout at the junction with the A46, around 4.20pm.
Leicestershire Police said: "The VW Polo overturned and came to rest on the entry slip road to the A46 on the southbound carriageway. The driver sustained a serious arm injury and was taken to hospital. No one else was injured.
"Officers would like to speak to anyone who may have witnessed the collision or saw either vehicle beforehand. If anyone has video recording equipment installed in their vehicles and was driving in the area around this time we would ask that they check the footage and get in touch if they captured any aspect of the incident.
"We also believe there was a white car driving immediately behind the vehicles involved and the occupants may have witnessed what happened. If that was you please contact us."
Anyone with any information is asked to contact PC 4190 Steve Isherwood on 101 or via www.leics.police.uk, quoting crime number 24*274165.