A man threatened staff with a knife and stole money from a till in a robbery at Budgens, Wolverton.
At around 7.40pm on Sunday (January 6) a man entered the Budgens store on Addington Avenue and demanded money from the till.
The offender stole cash from the till and then left the store.
No-one was injured during the incident.
The offender is described as a black man, he was wearing dark clothing and a camouflage baseball cap.
Investigating officer Detective Constable Ian O’Bryne, based at Milton Keynes police station, said: “I am appealing for anyone who may have witnessed this concerning incident or anyone who has any information that may assist with this investigation.
“If you live or work nearby and have CCTV, please review the footage from Sunday evening and get in contact with us if you have anything which could help with the investigation.
“If you have any information that could help, please get in touch using our online form or by calling the non-emergency number, 101. You will need to quote reference number 43190005222. Alternatively, you can contact Crimestoppers anonymously on 0800 555 111.
“This incident is not currently being linked to similar offences in the area but we are keeping an open mind.”
If you own or work in a business in the area, you can find advice on how to protect your business from burglary on our website or by visitinghttps://www.thamesvalley.police.uk/cp/crime-prevention/business-robbery/protect-your-business/