West Mercia Police is appealing for witnesses to the armed robbery at the One Stop, Trench Road, on Saturday night.
A man is reported to have entered the shop at about 9.40pm and pointed a weapon – believed to be a hammer – at a staff member before demanding money from the till.
An unknown amount of money was taken and the man left the store in the direction of Stanmore Drive.
He is described as in his 20s, about 5’6 and of very slim build.
The man was wearing a black hoodie, blue jeans, black shoes, black ski goggles and white gloves.
Officer are particularly keen to speak to a passer-by who is understood to have seen someone getting into a vehicle near the building.
Anyone with information should call police on 101 with the incident number 720S of November 24.
Alternatively, contact Crimestoppers anonymously on 0800 555 111.