MOSCOW, July 8 (RAPSI) – The Federal Security Service’s (FSB) investigators will examine former Yukos security chief Alexei Pichugin sentenced to life in prison of masterminding several murders on July 13, RIA Novosti reported on Friday citing his attorney Ksenia Kostromina.

The subject matter of interrogation has not been disclosed by investigators, Kostromina added.

Earlier, Pichugin was transferred to Moscow from the colony in the Orenburg region, commonly known as the Black Dolphin Prison.

According to investigators, a criminal group killed several people between 1998 and 2002, including Petukhov, on orders from former Yukos shareholder Leonid Nevzlin. In 2009, Nevzlin, who moved to Israel in 2003, was sentenced in absentia to life in prison.

Pichugin was found guilty of murdering Petukhov and received a life sentence in 2008.

The murder of Petukhov provoked a public outcry 17 years ago, when several media outlets speculated that he was directly involved in the re-division of Russia’s oil assets. Investigation into Petukhov’s murder was suspended.

In December 2015, former Yukos owner Mikhail Khodorkovsky was charged with organizing the murder of Petukhov. The Basmanny District Court of Moscow issued an arrest warrant for Khodorkovsky and put him on the international wanted list.