BTC-e is Russia based exchange operator which was accused by the FinCen enforcement law authorities for money laundering and being linked with drug sales, AML and stole bitcoins from MtGox. Their
press release says:
BTC-e also processed transactions involving funds stolen between 2011 and 2014 from one of the worlds largest bitcoin exchanges, Mt. Gox. BTC-e processed over 300,000 bitcoin in transactions traceable to the theft. FinCEN has also identified at least $3 million of facilitated transactions tied to ransomware attacks such as Cryptolocker and Locky. Further, BTC-e shared customers and conducted transactions with the now-defunct money laundering website Liberty Reserve.
How is that a Russian-based exchange could be shut down by US authorities? What are the basis to do it?