A BP garage in Hertfordshire was reportedly robbed at gunpoint in the early hours of the morning.
The petrol station in Luton Road, Harpenden, was targeted around 4am by a man dressed in dark clothing.
He brandished what would have been a gun before demanding money.
Detective Sergeant Adam Haines said: “Fortunately the staff were unhurt in the flight but understandably they were very shaken by the threat of violence.
“We are now carrying out thorough investigations to find the person responsible, which includes the use of the police helicopter, the armed intervention unit and specially trained dogs.
“We will also be doing house-to-house surveys in the area to see if anyone saw or heard anything suspicious prior to the theft.”
Neighborhood Inspector Andy Wiseman added: “This is a highly unusual incident and whilst residents will be rightly concerned, please be reassured that we have a large police presence in Luton Road and are doing our utmost to possible to find the offender.”
Information can be reported online or via 101 quoting reference 41/95207/22.
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