POLICE are asking shop and bank staff to be on their guard after two supermarket managers were tied up by knife-wielding robbers.

The men were locking up at Lidl in Margate Road, Ramsgate on Friday night when two men approached them.

One of them got out a knife and demanded they went back inside the shop.

Once inside, the store manager was forced to open the safe, and hand over a large quantity of coins.

The men were then tied to a chair while the robbers escaped. Staff working at the nearby Westwood Bus Depot saw the men run along the side of the shop and out towards the bus garage. The managers were uninjured.

A police spokeswoman said: "We would ask for banks and shops to look out for people paying for goods with large quantities of coins, or looking to exchange them."

Police have issued descriptions of the two men. The first was white and in his early 20s, 6ft, with short blond hair. He was wearing a light coloured top and blue jeans.

His accomplice was around 5ft 6in, with cropped hair. He was wearing T-shirt with horizontal stripes and a scarf around his neck.

Anyone with information is asked to contact DC Nick Borda at Margate Police Station on 222035.