Shares of Russian businessman Oleg Tinkov's credit card supplier TCS plummeted Friday after the US Department of Justice charged its founder with fraud and demanded his extradition from Britain.

Tinkov stands accused of concealing $1 billion in assets and income from the US tax authorities at the time when he renounced his US citizenship in 2013, which required him to report his assets following a stock market flotation in London, the Department of Justice said Thursday.

"The indictment charges that Tinkov filed a false 2013 tax return" and he faces a possible six years in prison if convicted, it said.