A 74-year-old man was allegedly assaulted by two men after a row in Tesco Extra, Batley.
The man and his wife were in a confrontation with a woman and her husband, both in their sixties, and her adult son.
It has been claimed the 74-year-old was then assaulted by the two men, suffering minor injuries.
Police are investigating the circumstances of the alleged assault, which took place around noon on Thursday July 11.
Anyone who witnessed the incident at the Bradford Road store or has information is asked to contact PC Danny Walker at the Batley and Birstall Neighbourhood Policing Team (Team 1) on 101 or Crimstoppers anonymously on 0800 555111.