Armed police raided the Moscow headquarters of a bank owned by Russian media and banking tycoon Aleksandr Lebedev on November 2.
An aide to the businessman, Artyom Artyomov, said Lebedev was in his National Reserve bank when up to 30 armed Moscow city police officers surrounded the building and entered the premises.
"What do these people want and why did they come here? And why are they doing it in such an appalling way? Why do they have to put on a show? Can't they just come and ask for a particular document?" Aryomov said.
Artyomov explained that if the police had asked, they would have been given any of the documents they requested.
The bank later issued a statement saying police had produced a court order for the search in connection with transactions made by one of the bank's clients in 2008.
A Moscow police spokesman confirmed the raid but gave no further details.
Lebedev co-owns, together with former Soviet president Mikhail Gorbachev, the Russian opposition Novaya Gazeta.
He also owns the British Evening Standard and The Independent, and his companies hold stakes in Aeroflot and Gazprom.
compiled from agency reports