Federal prosecutors charged Samurai Wallet founders Keonne Rodriguez and William Lonergan Hill with conspiracy to commit money laundering on Wednesday, as the U.S. government continues its approach to prosecuting crypto mixing tools that may be used by illicit actors and foreign governments to hide fund transfers.

According to a press release issued Wednesday, the pair developed, marketed and operated the mixer, which “facilitated more than $100 million in money laundering transactions from illegal dark web markets.”