Police are trying to trace a man who was seen committing an indecent act in Deanshanger High Street on July 6.
The incident happened between 3.20pm and 3.50pm. The man was sitting in a white Astra type small van or estate car.
He is described as white in his late 40s of heavy build with short grey and black hair, stubble and bald on the top of his head. He was bare chested or possibly naked.
Witnesses to this incident, or anyone with information, should call Northamptonshire Police on 03000 111 222 - alternatively, information can be given anonymously to Crimestoppers on 0800 555 111.