Police are appealing for witnesses after armed robbers struck at two Snax 24 sites in apparently unrelated incidents.
A knife-wielding robber targeted the Snax 24 on Ormesby High Street, Middlesbrough, at 1.30pm on March 20.
Police said a man walked into the petrol station and demanded cash. He then produced two knives and escaped with a small amount of cash, cigarettes and alcohol.
There were several other customers in the shop at the time.
The man is described as white, 5ft 9in tall and of a slim build. He was wearing a blue or grey jacket, blue jeans and white trainers and was carrying a black gym bag.
Anyone with information is asked to contact Detective Sergeant Chris Stone at Cleveland Police on 101, or Crimestoppers on 0800 555111.
West Midlands Police are appealing for information after staff delivering cash to Snax 24 on Pedmore Road in the Brierley Hill area of Dudley were threatened by armed thieves.
Officers were called to the petrol station just after 6.30am on 19 March.
Two men armed with hammers threatened the delivery staff before fleeing empty handed.
It is believed the masked men, who were wearing grey tracksuits, sped away in a car which is described as a blue Audi.
Detectives from Dudley police station are appealing for witnesses and to anyone who may have seen the blue Audi before or after the robbery to come forward.
Sergeant Michael Greenland, from Dudley CID, said: “Fortunately no members of staff were injured but they were left very shaken by the ordeal.
“We are interested in speaking to anyone who saw the movements of the Audi before or after the robbery and are appealing to any witnesses to come forward.
“If anyone has any information they are urged to call 101. Alternatively people can leave information anonymously by contacting Crimestoppers on 0800 555111.”