A cryptocurrency “mine” which was stealing electricity worth thousands of pounds has been uncovered in the West Midlands.

Police said they executed a drugs warrant at an industrial estate in Sandwell on May 18 after receiving intelligence that the site was being used as a cannabis farm.

But the West Midlands force said it instead found a huge bank of around 100 computer units as part of what is understood to be a Bitcoin mining operation.

Cryptocurrency mine
The operation was uncovered by police at an industrial unit in Sandwell (West Midlands Police/PA)

The IT equipment was seized from the building in the Great Bridge Industrial Estate and inquiries with Western Power revealed the electric supply had been bypassed.

A cryptocurrency is a digital currency which has transactional records stored and secured through cryptography processes, meaning it is virtually impossible to counterfeit. Bitcoin mining is the process by which new Bitcoin are created and entered into circulation, done by computers solving complicated puzzles, which takes huge amounts of power.

Police said they had received reports that people were visiting the unit at different times of day – adding that lots of wiring and ventilation ducts were visible.

A police drone also picked up a considerable heat source from above which the force described as “classic cannabis factory signs”.

Sandwell Police Sergeant Jennifer Griffin, said: “It’s certainly not what we were expecting.

“It had all the hallmarks of a cannabis cultivation set-up and I believe it’s only the second such crypto mine we’ve encountered in the West Midlands.

“My understanding is that mining for cryptocurrency is not itself illegal, but clearly abstracting electricity from the mains supply to power it is.

“We’ve seized the equipment and will be looking into permanently seizing it under the Proceeds of Crime Act.

“No-one was at the unit at the time of the warrant and no arrests have been made – but we’ll be making inquiries with the unit’s owner.”

The warrant was one of almost 50 executed as part of County Lines Intensification Week, which led to 84 arrests, significant drug seizures and the recovery of weapons including a sawn-off shotgun and a blank firing pistol converted to discharge live rounds, the force said.