The central Moscow headquarters of aluminum giant RusAl were raided by investigators Tuesday as part of allegations of massive tax evasion at its foil-making subsidiary.
The materials uncovered during the raid will be added to the case files, the Investigative Committee's Moscow branch said on its website.
The raid was based on "groundless claims" by tax authorities and the Investigative Committee against RusAl Foil and its management, the aluminum producer said in a statement on its website.
"The Moscow Arbitration Court decision on which the claims are based has not come into effect and will be appealed by the company," the statement said.
The Investigative Committee opened a probe earlier this month into RusAl Foil chief executive Igor Kasyanov on suspicion that he evaded more than 200 million rubles ($6.5 million) in income and value-added taxes.
Investigators suspect Kasyanov of providing fake information on RusAl Foil expenses attributed to its cooperation with a bogus firm purportedly used to evade taxes between 2008 and 2009.
The parent company denies those allegations.