The European Court of Human Rights concluded that the Kremlin was behind the 2006 poisoning of former KGB spy Alexander Litvinenko, who had defected to the West and was residing in the UK at the time of the attack.

Litvinenko succumbed of the highly-lethal polonium-210 compound found in his blood following a post-mortem examination.

According to an NPR News report, the ECHR said it "[could not] but conclude" that two Russian intelligence agents, Andrei Lugovoi and Dmitry Kovtun, were behind Litvinenko's murder while at the same time rejecting punitive damages sought by the former spy's widow.

The Kremlin has consistently denied any wrongdoing in Litvinenko's death, while Lugovoi and Kovtun have suggested that the defector may have poisoned himself.

In a related report, British authorities said they had identified a third suspect in a nerve agent attack on a former Russian double agent who had also fled to England.