A gang of five masked men threatened staff at a Nottingham store before fleeing with cash and cigarettes.
The thieves raided the Co-op in Mansfield Road, Carrington, as it was closing at 2200 BST on Sunday.
Police said they threatened members of staff and demanded they open the safe. The gang then stole an undisclosed amount of cash and cigarettes.
Four of the men were white and one was described as being of mixed race, all wore dark clothing.
The men were aged about 20 and had their faces covered with either hooded tops or balaclavas.
Police are examining CCTV images and have appealed for any witnesses to contact them.