MOSCOW, July 13. /TASS/. Russia’s Federal Security Service (FSB) questioned former security chief of the now defunct Yukos oil giant Alexei Pichugin who was sentenced to life imprisonment for organizing several murders, Pichugin’s lawyer Ksenia Kostromina told TASS on Wednesday.

"Alexei Vladimirovich Pichugin’s stance has not changed during the latest interrogation. Mr. Pichugin believes he was unjustly convicted and is not guilty of any of these criminal charges," Kostromina said.

The attorney did not disclose about which criminal case, Pichugin had been questioned, citing attorney client privilege.

A source familiar with the issue told TASS earlier that Pichugin had been transferred to Moscow from a penal colony to be questioned about the 1998 murder of Nefteyugansk mayor, Vladimir Petukhov.

As part of this criminal case, charges were also brought in absentia against former Yukos CEO Mikhail Khodorkovsky. However, TASS has not received yet any official comments from law-enforcement agencies.

Pichugin was sentenced to 20 years in a maximum security penal colony in 2005 for organizing the double murder of a married business couple from Tambov, Olga and Sergey Gorin. He also was convicted of the attempted murders of Rosprom administrator, Viktor Kolesov and Moscow City Hall spokeswoman, Olga Kostina.

In a second trial that followed, Pichugin was found guilty of organizing three additional killings and four attempted murders. Among them, the homicides of Nefteyugansk Mayor Vladimir Petukhov and Moscow businesswomen, Valentina Korneyeva, who was seen as a threat to Yukos’ interests. Consequently, Pichugin was sentenced to life imprisonment.