Police are appealing for witnesses following an attempted robbery at a petrol station in Chell, Stoke-on-Trent at approximately 10.30pm last Friday.
A man entered the Murco site in Biddulph Road, armed with what was described as a kitchen knife.
He verbally threatened the male shop assistant and demanded cash. Apparently the assistant used a fire extinguisher to ward off the offender and he fled the scene empty-handed. Fortunately the shop assistant was not injured and nothing was stolen.
An investigation into the incident, which happened just before closing time, is now underway and officers are appealing for information.
The offender was wearing a balaclava, sunglasses, thick jacket, gloves and trousers. All items were black.