The founder of a now-defunct bitcoin mining company is in hot water over claims that his companies defrauded investors out of $20 million in a Ponzi scheme.

On Tuesday, the U.S. Securities and Exchange Commission filed a civil complaint against Homero Joshua Garza and his companies, GAW Miners LLC and ZenMiner LLC, which they claimed “used the lure of quick riches from virtual currency to defraud investors.”

According to the complaint filed in federal court in Connecticut, Garza sold $20 million worth of shares in a digital mining contract to more than 10,000 investors between August and December 2014. The contracts, or “Hashlets,” were touted as “always profitable and never obsolete.”

“Most Hashlet investors never recovered the full amount of their investments, and few made a profit,” the commission said in a statement.