A man has been treated for facial injuries in hospital after he refused to hand money over to a group in Grimsby.
The cashpoint robbery happened outside Asda on Corporation Road between 12.20am and 12.42am on Monday, October 24.
A 42-year-old man withdrew money from the cash machine when he was approached from behind by an unknown man who demanded the cash.
The victim refused and defended himself before two further men approached and assaulted him, before taking the cash.
The man sustained facial injuries and was taken to hospital for treatment.
Officers would like to speak to anyone who witnessed the incident or have information pertinent to the investigation.
They are urged to call 101 quoting crime reference number 2223636 or Crimestoppers anonymously on 0800 555 111.