A group of about five teenagers threw stones at a car driving between the Carlsberg factory and the railway bridge.
The incident happened at about 4pm along Mill Lane on Tuesday, March 28, Northamptonshire Police today revealed.
They are described as secondary school age boys, one around 14 years old, black, with a "square cut hairstyle" and wearing a black blazer.
Two others are described as short, black and wearing hooded tops and the other as two as white "boys."
Witnesses can contact police on 101 or Crimestoppers anonymously on 0800 111 555.