At 9.26pm on 28 April three men entered the convenience store in Admirals Road and threatened staff with weapons.
The men then fled with a quantity of cash.
DC Darren Burns said: “While the staff were unharmed it was a traumatic ordeal for them so it’s vital we find those responsible.
“We are making a number of enquiries to identify the suspects and would ask anyone who saw the incident, or any suspicious vehicles near the shop to contact us. Also if you were in the area at the time and have dashcam footage, please get in touch.”
Anyone with information should contact Cheshire Police on 101 or via https://www.cheshire.police.
If you have dashcam footage you can submit it via https://www.cheshire.police.
Alternatively information can be given anonymously by contacting Crimestoppers on 0800 555 111.