Controversial businessman Viktor Baturin, brother of the ex-Moscow mayor's billionaire wife Yelena Baturina, was detained for allegedly trying to sell fake promissory notes issued by her former companies, Izvestia
Baturin tried to sell the notes, allegedly issued by Inteko and Inteko-Agro and worth a combined 5.4 billion rubles ($172 million), to an unspecified British company, the report said.
Another promissory note by Inteko, worth 250 million rubles ($7.9 million), was offered to the Rosagrolizing agriculture company.
But that note was never registered with the state, which prompted investigators to open an inquiry.
Baturin tried to sell the promissory notes this spring, but investigators only moved to have him detained Monday, Interfax said.
Inteko's press office confirmed that at least one promissory note in the case was never issued by the company, but declined to elaborate.
Baturin, who was charged with attempted fraud, punishable by up to 10 years in prison, said he received the fake bill from his sister, Lenta.ru reported. Yelena Baturina did not comment Tuesday.
There is no love lost between the Baturin siblings, who had a falling-out over Inteko's shares in the 2000s. When Baturina sold Inteko to Binbank CEO Mikhail Shishkhanov for an alleged $1.2 billion in September, her brother challenged the deal in court.
Federal authorities opened an embezzlement case against Baturina after her husband, Yury Luzhkov, was ousted from City Hall last fall. The pair says the case has been fabricated, and Baturina, who moved to London, has so far dodged summonses for questioning.
Baturin on Tuesday linked the case against him to the crackdown on his sister and Luzhkov, but Inteko denied any connection, Interfax said.