Jewellery and cash were stolen from the private quarters of a shop in Shelley Street, Northampton, on Friday.
A group of approximately six men entered the shop and while some members of the group distracted the shop worker, others went upstairs and entered the private property.
The group of men were aged between 25 and 40, all had dark coloured hair, some wore sunglasses and all spoke with foreign accents.
The incident took place between 3.20pm and 3.50pm.
Police would like to speak to anyone who may have witnessed this incident or who may have any information regarding it.
Witnesses or anyone with information about this incident is asked to contact police on 101 or Crimestoppers anonymously on 0800 555 111.