Vandals damaged a car after they threw stones from a bridge over the A45 in Northampton.
A black Ford Fiesta, driven by a 28-year-old woman, was travelling westbound along the A45 between Billing and Riverside on Monday, when it was hit by a large stone, believed to have been thrown from a bridge over the dual carriageway.
The incident happened between 3.45pm and 4pm.
Witnesses, or anyone with information, are asked to call Northamptonshire Police on 101. Alternatively, they can call Crimestoppers on 0800 555111.