A boy was pushed to the floor by a man at Weston Favell Shopping Centre in Northampton.
A 14-year-old boy was with a group of friends at the shopping centre on Monday when they were approached by a middle-aged man after the emergency button on the ‘auto-walk’ was pressed.
The man then swore and pushed the boy, knocking him off his feet.
The man, who was with a white, middle-aged woman, then left the shopping centre and was seen driving out of the car park in an old-shape black Renault Clio.
The man is described as white, with a stocky build and aged in his 40s to 50s.
The assault happened on Monday between 5.50pm and 6.20pm.
Witnesses, or anyone with information, are asked to contact Northamptonshire Police on 101. Alternatively, information can be given anonymously to Crimestoppers on 0800 555 111.