Masked men threatened a shop worker and a customer during an attempted robbery at a Sheffield supermarket.
Detectives believe the men were carrying a knife and possibly a small gun when they entered Savemore Wincobank in Fife Street at around 6.50pm on Saturday.
They made threats to people inside the shop and demanded cash.
A South Yorkshire Police spokesman said: "No one was injured during the incident, however damage was caused to the shop and, as a result, the shop assistant suffered minor injuries.
"The offenders left empty handed and ran from the shop, heading towards Merton Lane.
"Investigating officers want to hear from you, if you know who is responsible or if you were in the area at the time and saw the men enter or leave the shop."
Phone police on 101, quoting incident number 891 of 6 May 2017, or Crimestoppers anonymously on 0800 555 111.