A Greek court in Thessaloniki ruled last week that the creator of a shady bitcoin exchange under investigation by American authorities will be extradited to France rather than to the United States or to his native Russia.

Last summer, federal authorities identified Alexander Vinnik as a central figure in the massive bitcoin theft that was a major factor in the downfall of Mt. Gox, the Japanese bitcoin exchange that led the market in bitcoin's early years. If Vinnik is ultimately determined to be involved in the crash and eventual bankruptcy of Mt. Gox, that revelation would finally solve what has remained one of the bitcoin community's biggest mysteries.

American prosectors have previously said that the exchange, BTC-e, was behind around $4 billion worth of money laundering.

"BTC-e was an international money-laundering scheme that, by virtue of its business model, catered to criminals and to cybercriminals in particular," prosecutors wrote in the indictment of Vinnik. "Through VINNIK's efforts, BTC-e emerged as one of the principal means by which cybercriminals around the world laundered the proceeds of their illicit activity. BTC-e facilitated crimes, including computer hacking and ransomware, fraud, identity theft, tax-refund fraud schemes, public corruption, and drug trafficking."

In a statement, the Russian Foreign Ministry said that sending Vinnik to France would "continue to complicate [Greece's] relations with Russia" and that Moscow would not "leave these actions unanswered."

Previously, the Greek Supreme Court had ruled in favor of his extradition to the United States, but it remains unclear why a lower court has now ruled that Vinnik should be sent to France, where authorities there say he defrauded around 100 French citizens.

The Greek minister of justice will now reportedly have the final say as to where he will be sent: France, Russia, or the United States.

American authorities aren't saying much about the Vinnik case for now.

"We will decline to comment," Wyn Hornbuckle, a DOJ spokeswoman, emailed Ars.