Alexander Vinnik, one of the operators of the former crypto exchange BTC-e, pleaded guilty to money laundering conspiracy, the US Department of Justice announced.

Vinnik ran BTC-e from 2011 to 2017, during which time the exchange processed more than 1 million users transacting over $9 billion in cryptocurrency.

BTC-e was linked to a hacker attack on the now-defunct crypto exchange Mt. Gox after about 300,000 BTC was laundered through it. Vinnik was arrested in Greece and went through a lengthy extradition process, as a result of which he was extradited to the United States.

The BTC-e exchange did not register its activities in the United States, did not comply with KYC and AML rules, and did not collect customer data. Vinnik used shell companies to process fiat conversions for BTC-e.

Vinnik is directly responsible for losses of $121 million.