Keonne Rodriguez and William Lonergan Hill, the founders of Samourai Wallet, have been detained by the U.S. Department of Justice for allegedly laundering over US$100 million and operating an unlicensed money-transmitting service.

The arrests are part of a concerted international law enforcement operation targeting the illicit use of “cryptocurrency mixers.”

The service provided by Samourai Wallet, which has been downloaded more than 100,000 times, was designed to conceal users’ financial activities and has been implicated in over $2 billion of illegal transactions, the United States Attorney’s Office Southern District of New York said in a press release.

The investigation into Samourai Wallet, which offered privacy-enhancing features, involved multiple agencies including the IRS, FBI, and Europol.

Authorities have removed the app from the Google Play Store in the U.S.

The founders, who allegedly promoted their service to criminals and sanctioned individuals, were arrested in Pennsylvania and Portugal, with Hill awaiting extradition to the U.S.

Crypto industry members took to social media to express their discontent about the arrests.

“Shocked and saddened by the news about Samourai Wallet today. It is one of the biggest failings of this industry that in 15 years we still didn’t find a way for people to maintain their privacy legally. PRIVACY IS NORMAL,” Udi Wertheimer, co-founder of Taproot Wizards said on X.

Other industry participants have suggested spinning up a “defense fund” for Samourai Wallet.