A pair of balaclava clad men punched a cashier in the face before fleeing with cigarettes and money.
At around 7.40pm on February 16 two men entered Norton Heath petrol station in Chelmsford Road, Ongar and punched a member of staff in the head.
The victim was also grabbed as the men demanded money and cigarettes.
They left the scene with a three-figure sum of cash and cigarettes in a Volkswagen Golf, which was parked on the forecourt during the incident.
One of the men is described as being 6ft, of a stocky build and wore a matching dark grey tracksuit top and bottoms.
The other man was of a medium build and he wore a light grey tracksuit top and bottoms.
Police are looking to hear from anyone who has information and dash cam footage.
Please call Loughton police station on 101 quoting crime reference 42/25808/19 or Crimestoppers anonymously on 0800 555 111.
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