A coach was hit by a drinks can which was dropped from a bridge in Wellingborough.
The incident took place at about 4pm on Monday, June 19. Police have today (Thursday) issued an appeal for witnesses.
Three 11 to 12-year-old boys were seen leaning over the footbridge over the A509.
They dropped a drinks can which hit a coach driving under the bridge.
Nobody was injured in the incident.
Officers would particularly like to speak with a witness who reported the incident at the time and anyone who was in the area at the time.
Anyone who has information should contact police on 101 or Crimestoppers anonymously on 0800 555111.