Unexplained deaths of UK-based Putin critics starting to mount up
Nikolai Glushkov was always adamant that his friend Boris Berezovsky had not taken his own life.
The idea that the oligarch and self-appointed chief nemesis of Vladimir Putin had committed suicide was, he insisted, "bullshit".
"I will never accept the idea," he said after coroners recorded an open verdict in his fellow exile's death in Berkshire in 2013.
Five years on, the same questions will be asked of his own death. Glushkov, who was 68 when he died on Tuesday, rose to wealth in the 1990s as a lieutenant of Berezovsky, the oligarch who amassed immense wealth and influence under Boris Yeltsin's government but fled to Britain after falling out with Vladimir Putin.
The two men would later become part of a London-based coterie of fugitive Russian businessmen and critics of Mr Putin that has been wracked by unexplained deaths.
Besides Berezovsky and Glushkov, the network included Badri Patarkatsishvili , a Georgian businessman who died in 2008, apparently of a heart attack.
And they had close links not only to Alexander Litvinenko, the former Russian spy assassinated in London and 2006, but also to Andrei Lugovoi - the man Scotland Yard believe carried out that murder.
Boris Berezovsky made his fortune via a combination of sharp operating in the car dealing trade and snapping up state-owned enterprises in the aftermath of the Soviet collapse. On his rapid rise to phenomenal power and wealth, Berezovsky had no closer confidante, said Sergei Migdal, a former Israeli Secret Service officer who worked in Berezovsky's Israeli office from 2005 to 2010.
"Glushkov has known Berezovsky since the 1980s. He was one of the few people who was close to Berezovsky during the 90s and was involved in many of his business dealings. "They were also very close friends," Mr Migdal said.
Among their most prominent joint projects were AvtoVAZ, the car maker that produces the Lada, and Aeroflot, Russia's national airline, which Glushkov ran for Berezovsky as its financial chief.
Meanwhile, Berezovsky had acquired another loyal lieutenant - a KGB officer called Andrei Lugovoi who took leave to work as the oligarch's personal bodyguard.
By the end of the 1990s, Berezovsky, with Glushkov at his side, was wielding immense political power. He controlled Russia's main television channel, Channel One, sat on Boris Yeltsin's security council, and is said to have been instrumental in choosing Putin as Yeltsin's successor in 1999.
But when the oligarch dramatically fell out with the new president in 2000, Glushkov's fortunes changed too. While Berezovsky fled Russia for France, Glushkov was charged with defrauding Aeroflot and slung into Lefortovo prison, the top-security facility used by Russia's Federal Security Service.
That led to one of the most bizarre incidents in the saga.
"The general consensus is that Glushkov was kept hostage [by the authorities] because they really wanted to get Boris," said Mr Migdal. "And the suspicion was that Berezovsky asked Lugovoi to spring Glushkov from prison."
Glushkov later denied knowledge of the botched escape attempt, which some allies of Berezovsky have claimed was staged as a pretext to extend his jail term.
Whether he was in on it or not, the plan went drastically wrong, and Mr Lugovoi found himself serving time. Both men were later released. But while Mr Lugovoi stayed in Russia, Glushkov joined his business partner in Britain.
In 2017, Glushkov was convicted in absentia on fresh charges of defrauding Aeroflot of $123m. He was sentenced to eight years in jail. He always denied the charges.
Berezovsky and another close associate, Yuli Dubov, had been granted asylum in Britain in 2003.
The decision caused fury in the Kremlin, which saw the move as a political decision to harbour government critics.
That antagonism only increased when Berezovsky used his exile to style himself as Mr Putin's most vociferous critic, openly saying he wanted to overthrow the president.
The antagonism came to a head in 2006 when Litvinenko - another former KGB man and close associate of Berezovsky - was murdered in London with Polonium 210, in what the British government believes was an assassination "probably" ordered by Mr Putin himself. Scotland Yard believes Mr Lugovoi carried out the killing, in a dramatic inversion of his former loyalties. Mr Lugovoi, who is now a Russian MP and a supporter of Mr Putin, has always denied the charge.
There followed a series of unexplained - but far less clear-cut deaths. Two years later Patarkatsishvili, the Georgian businessman, collapsed at his Surrey mansion the evening after a meeting with Berezovsky, Glushkov, and Mr Dubov.
Berezovsky was found hanged at his own home in 2013 in an apparent suicide. With Glushkov's death, Mr Dubov is now the only survivor of that meeting.
Foul play has not been established in any of those deaths. Some associates of Berezovsky have contested Glushkov's insistence that is was not suicide, saying the oligarch had become a recluse after the humiliating collapse of his attempt to sue the oligarch and Chelsea owner Roman Abramovich in the London High Court in 2013. (© Daily Telegraph London)