Police are investigating the theft of cash from an ATM at Kirkby Stephen, during which an explosion was caused to allow the thieves to get at the machine.
The theft – carried out by a group of men in a white van – happened in the early hours of Saturday (SEPT 15) at the Co-op shop in North Road.
They caused the explosion before forcing their way into the store and stealing some of the contents of the damaged machine.
Nobody was hurt and police have stressed this type of crime is rare in Cumbria.
Some of the stolen money will have been damaged by the explosion.
Shopkeepers and business staff are being asked to look out for money that is scorched or damage – and to contact police if they spot any.
People are also being urged not to approach if they have any suspicion that an ATM is being tampered with in this way, to keep their distance and dial 999.
Detective Sergeant Matthew Belshaw said: “The offenders have employed a dangerous and unpredictable technique that involves first pumping gas into the front of the ATM, via a canister, before igniting the gas and causing an explosion.
“This technique is not only extremely dangerous to the criminals employing it but also to any members of the public who may be nearby, or unsuspecting workers who may be present within the targeted establishments.
“Fortunately on this occasion no one was hurt or injured and these crimes are still rare.
“This incident has been opportunistic and has taken place when the store has been empty and at a time when there has been no one around.
“It is known, due to the heat of the explosion, some of the stolen money is damaged.
“Cumbria Police are asking all shopkeepers and establishments to be conscious of receiving any money that is scorched or damaged and to make contact if they have.”
Work is underway, including forensic investigations and work with other forces.
Police are appealing to any witnesses who may have any information about this offence to come forward.
Officers have asked the public to contact them if they see anyone acting suspiciously near a bank or ATM as any information could be vital.
Similar offences across the country have involved the offenders hiding their gas canisters nearby in preparation, before disposing of them nearby afterwards.
Police are urging anyone with any information to contact officers on 101 or call Crimestoppers anonymously on 0800 555 111. ALWAYS call 999 in an emergency or where a crime is in progress.