Russia’s Federal Security Service said it found artworks by Pablo Picasso and Rembrandt and documents for offshore companies belonging to self-exiled investor Boris Berezovsky in a raid on an illegal gambling operation in Moscow.

The paintings, worth more than $5 million, and documents were found in the main office of a building in central Moscow that was once used by Berezovsky, said the FSB, as the main successor to the Soviet-era KGB is known, on its website.

The crime syndicate that operated out of building No. 40 on Novokuznetskaya Ulitsa was able to earn as much as $10 million a month in part because of the “support” it received from senior law enforcement officials in the Moscow region, including a first deputy prosecutor, the FSB said. The building also houses the Triumph art gallery.