An Ohio man has been arrested by federal authorities for running a “Bitcoin mixer” service on the dark web that helped to launder as much as $300 million in Bitcoin. The bitcoin allegedly laundered by the service are now worth $3.5 billion at the current valuation.

ZDNet reports that Larry Harmon, 36, of Akron, Ohio, has been accused of operating a website on the dark web called “Helix” which acted as a “Bitcoin mixer” service, disguising the origin of users’ Bitcoin transactions to make them untraceable. Because the Bitcoin blockchain is a public database, transactions on it can often be linked back to the buyer’s credit card, bank account, or PayPal, Helix sought to prevent that.

Helix acted as a service that would take funds from a user, split it into smaller amounts and then reassemble the funds at a new Bitcoin address via thousands of small transactions. This is done in an attempt to mask the origin of the first transaction. Don Fort, Chief, IRS Criminal Investigation, said in a DOJ press release:

The sole purpose of Harmon’s operation was to conceal criminal transactions from law enforcement on the Darknet, and because of our growing expertise in this area, he could not make good on that promise. Working in tandem with other sites, he sought to be the ‘go-to’ money launderer on the Darknet, but our investigators once again played the role of criminal disrupters, unraveling the interlinked web from one tentacle to another.

The DOJ also claims that Harmon ran Helix as a secondary project to his dark web drug listing search engine “Grams.” Grams allowed users to search for and find the cheapest drugs on the dark web, while Helix was advertised as a way for users to anonymize their drug purchasing funds.

According to the DOJ, Harmon operated Helix since 2014 and helped launder more than 350,000 bitcoins. At the time the transactions were made, the Bitcoins were valued at around $300 million, today they would be worth approximately $3.5 billion.

Lucas Nolan is a reporter for Breitbart News covering issues of free speech and online censorship. Follow him on Twitter @LucasNolan or email him at lnolan@breitbart.com