A Russian scientist has been fined the equivalent of $7,000 for using a supercomputer inside a secretive nuclear facility to mine for bitcoin cryptocurrency.

Denis Baykov, an employee of the Federal Nuclear Center in Sarov, was fined 450,000 rubles on September 17 after being found guilty of violating the lab’s internal computer policies, RIA Novosti reported via The Moscow Times, citing a ruling published by the city court.