Investigators said Thursday that they have opened a criminal case into Rosbank chief executive Vladimir Golubkov and bank senior vice president Tamara Polyanitsina on bribery charges.
Golubkov is suspected of having taken a bribe, while Polyanitsina has been named as an intermediary in the case.
"Golubkov, through his subordinate, demanded over $1 million from a commercial organization and received that amount in several installments from 2012 to 2013," said Investigative Committee spokesman Vladimir Markin.
Investigators believe that Golubkov demanded money from a businessman for reviewing the payment terms on his multimillion-dollar foreign currency loan with the bank.
Golubkov was detained at his office Wednesday in a dramatic raid filmed by the Interior Ministry and held overnight.
Golubkov, meanwhile, has denied wrongdoing, his lawyer Dmitry Kharitonov said Thursday.
He stressed that his client had been "illegally held in custody without being charged with a crime" from Wednesday afternoon until 6:15 a.m. Thursday.
Kharitonov said his client would have no comment to make about the case.
The Interior Ministry said Golubkov was detained while receiving 5 million rubles ($160,000) in cash as the last installment in a total payment of $1.5 million, which he allegedly demanded for his favors.
Rosbank, which is owned by France's Societe Generale, has not made any public comment about the investigation.
Golubkov has worked for the bank, Russia's ninth largest, since 1999 and was appointed CEO in September 2008.
If charged and convicted of extortion, he and the senior vice president face up to seven years in prison and stiff fines.