The US derivatives watchdog has filed charges against three separate cryptocurrency operators with allegations of fraud.
The Commodity Futures Trading Commission (CFTC), charged New York resident Patrick McDonnell and his company CabbageTech with fraud, saying the defendants "preyed on customers interested in bitcoin and litecoin".
In the second case, the CFTC alleged Dillon Michael Dean of Colorado and his UK-registered company Entrepreneurs Headquarters ran a Ponzi scheme, through which they solicited at least $1.1m (£793,000) worth of Bitcoin from more than 600 members of the public.
The third case remained sealed.
The move is the latest in a string of regulatory crackdowns against bitcoin and other cryptocurrencies elsewhere in the world.
In response to the first case, James McDonald, the CFTC’s director of enforcement, said: “This action is among the latest examples of the CFTC’s continuing commitment to act aggressively and assertively to root out fraud and bad actors involved in virtual currencies."
The CFTC gave the green light to bitcoin futures contracts in December, which were subsequently launched by CME Group and the Chicago Board Options Exchange the same month. According to Reuters, the agency came under criticism for not seeking wider industry feedback ahead of the approval.
South Korea, Japan and China all announced some form of regulatory crackdown this week in an attempt to address concerns of money laundering and fraud associated with digital currencies.
The US Securities and Exchange Commission (SEC) today said it has seen growing interest for exchange-traded funds (ETFs) that hold value in cryptocurrencies, but it warned it there are "significant" investor protection issues that still need to be looked at before such funds are offered to retail investors.
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