Five men have been arrested on suspicion of running crypto scams that may have cost victims more than £1m.
Detectives from the Met Police's economic crime team said the scams allegedly involved several websites claiming to offer pre-sale investment opportunities in new cryptocurrencies.
Investors were promised cash returns that could more than double in value when listed on major exchanges, according to the police.
However, the websites rarely had any intention to list them on exchange websites and could not guarantee returns in cash, the Met said.
A London-based "boiler room" operation was then suspected of making follow-up calls to victims to encourage further investment.
Victims of the scam, both in London and further afield, may have lost millions of pounds, according to the police.
The police named five websites allegedly linked to the arrests: DTX Exchange, Intel Markets, Cryptids, Algo Tech Trades and Unilabs Finance.
They warned that some of the sites previously operated under different domain names, which makes them harder to track.
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"These websites are highly convincing and use professional-looking content, fake endorsements and aggressive marketing tactics to lure people in," said Detective Sergeant Stephen Bourne.
"Once cryptocurrency is sent, it is almost impossible to recover. If you have any doubts, please do not invest.
"Though we are still very much in the early stages of the investigation, we believe this crime is affecting victims in every corner of the world and strongly advise members of the public not to engage with or invest through the websites listed," said DC Bourne.
The men, aged between 21 and 37, were arrested in London earlier this month on suspicion of conspiracy to commit fraud.
They have since been released on bail.
(c) Sky News 2025: Five arrested on suspicion crypto scam that may have cost victims millions
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