A major way criminals in the crypto world launder money is by sending digital assets across blockchains, bypassing a centralized service that can trace and freeze transactions. They use so-called cross-chain bridges to make it happen, and the dollar amounts are getting large.
“Tornado Cash is the typical first destination”\n\n To hide their trail, cyber thieves often use “mixers,” which let anyone deposit cryptocurrency and “mix” it with other people's cryptocurrency. Users can later withdraw the same amount they put in, but it's not the same cryptocurrency.