U.S. prosecutors have seized nearly $84 million from bank accounts and cryptocurrency wallets tied to a Montana payments firm linked to Tether.

The civil forfeiture targets Capstone, a money services business that allegedly posed as an information technology company to open accounts at major banks while moving money for crypto firms, reports Reuters.

Court filings say Capstone, registered in Montana, processed payments for two crypto companies through a bank in Dominica. Prosecutors say the firm also ran a scheme that converted fraud proceeds into crypto by posing as FBI agents.

Nearly $81 million was seized from Capstone accounts at Wells Fargo and about $2 million from an account at JPMorgan Chase. Roughly $1.2 million worth of Tether’s dollar-pegged token was taken as well, according to the July filing first reported by The Information.

Tether said it was a customer of the Dominica bank and that its assets there were limited. A spokesperson addressed Capstone’s alleged conduct.

“Tether had no knowledge of the conduct by Capstone alleged by the Department of Justice.”

The Justice Department did not allege wrongdoing by Tether or the other firms involved. Spokespeople for Wells Fargo and JPMorgan declined to comment.

A lawyer for Capstone told Reuters the firm denies wrongdoing and plans to challenge the complaint.