Unlike money held in a conventional bank account, cryptocurrency is often controlled directly by the owner through digital wallets or physical storage devices.

For criminals, that combination of speed, anonymity and irreversibility can make crypto holders attractive targets.

Whilst the vast majority of cryptocurrency theft happens online through hacks and scams, crypto investigators at Chainalysis say "wrench attacks" have surged in recent years.

According to their research, $30m (£22.6m) had been stolen so far this year up to June in violent robberies, making 2026 likely to become the single-worst year for violent crypto attacks on record. Home invasions are also on the rise this year, it found.

The US, Brazil, and Thailand are hotspots but France has seen the largest number of attacks by far, as a result of a data breach at a tax office that has apparently allowed wealthy crypto holders to be located.

"The physical security assumptions that protect traditional wealth, such as bank vaults and armored cars, do not automatically apply in crypto. Often, holders keep their assets in comparatively low security setups, like self-custody wallets, that can be compromised without any institutional gatekeeper standing in the way," said researchers in their report.

James said he became an amateur investor in crypto coins in 2020 and made enough money to quit his job in 2023 to trade full time.

Now he has lost everything and is looking to get back to his traditional job.

Police have yet to identify the attackers.

Crimestoppers is offering a £10,000 reward for information leading to progress in the investigation.

Alan Edwards from the charity hopes people might have information about the three attackers, the driver who was parked outside without a face covering, or the man on the phone.

"These criminals are obviously serious and part of some kind of organised crime gang," he said.

"People might be scared to give us information but we are independent of the police and keep people completely anonymous."

The three attackers are all thought to be in their late teens or early 20s and one of them was a black male with a scar under his left eyebrow.

James said he has little hope of recovering the stolen funds, but instead wanted to see those responsible brought to justice.

He also wants his experience to serve as a warning.

"They threatened my wife and my baby," he said. "People need to understand these risks are real."