Russia's Supreme Court has upheld a life sentence given to a former top security officer of the bankrupt Yukos oil company, who was convicted of murder and attempted murder.
The court Thursday turned down an appeal by lawyers for Alexei Pichugin, who had requested that the sentence be thrown out.
In August, a Moscow City court found Pichugin guilty of masterminding three murders and several attempted murders.
In 2006, he had been sentenced to 24 years in prison for organizing the 1998 killings of a prominent Moscow businesswoman, Valentina Korneyeva, and Vladimir Petukhov, the mayor of Nefteyugansk, at the center of Yukos operations. Pichugin had already been serving a 20-year sentence for another murder.
Last February, Russia's Supreme Court overturned the 24-year sentence and ordered a new trial.
Prosecutors say Pichugin carried out the crimes on orders from top Yukos shareholder Leonid Nevzlin, who now lives in Israel.
Critics of the prosecution have denounced government moves against Yukos as part of a plan to dismantle the giant oil firm in retaliation for the support the firm's former chief, Mikhail Khodorkovsky, gave to opposition political candidates.
Khodorkovsky and his business partner, Platon Lebedev, are serving eight-year terms in a Siberian prison following conviction of fraud and tax evasion.