The incident happened at around 8.40am this morning, 4 June, at the One Stop on Copnor Road.
An unknown man entered the store and made threats to staff before stealing the till.
As he went to make off the deadlock system activated locking the main door, he then smashed through a glass pane to leave the shop.
A second man was reported to be waiting outside with bikes.
The suspect was described as a man with a large build. He was wearing a black hoody, black trousers, a Nike bag, and a brown balaclava.
Were you in the area at the time? Perhaps you recognise the man in this image?
We understand that the image isn’t very clear, however we are hoping someone who knows him will recognise his clothing.
Anyone with information can phone 101 with reference 44210217261. Alternatively, you can call Crimestoppers 100% anonymously on 0800 555 111.