Europol, along with Dutch and Luxembourg authorities, have shut down one of the three largest cryptocurrency tumblers, Bestmixer.io
Source: https://cointelegraph.com/news/europol-shuts-down-200-million-crypto-mixing-service-bestmixer
Europol Shuts Down $200 Million Crypto Mixing Service Bestmixer
May 22, 2019
CoinTelegraph