A FORMER KGB agent accused of poisoning Russian defector Alexander Litvinenko was last night linked to a Russian businessman found dead in London.

Russian airline mogul Nikolai Glushkov, 68, was found with "strangulation marks" at his home in New Malden by his daughter Natalia on Monday night.

14 Nikolai Glushkov died at the age of 68, with Met Police now investigating his death Credit: Twitter

It has now emerged Andrey Lugovoy, widely accused of murdering dissident Litvinenko with polonium, was jailed for attempting to spring Glushkov from prison in 2001.

At the time, Glushkov was behind bars for defrauding Russian airline company Aeroflot.

Lugovoy was sent down for 14 months but had his jail term cut short.

There were claims that he may have owed the FSB for getting him out and poisoning Litvinenko's tea with a radioactive cocktail could have been part of his payback.

What we know so far:

14 Andrey Lugovoy, widely accused of murdering dissident Litvinenko with polonium, was jailed for attempting to spring Glushkov from prison Credit: AFP - Getty

14 Lugovoy was accused by Britain of putting polonium in Litvinenko's tea Credit: Getty Images - Getty

A blue tent obscured the entrance to the terraced house in New Malden, Surrey, as anti-terror officers investigated the "unexplained death" of Glushkov.

One neighbour said: "He was a wonderful man, the best neighbour you could ever hope for. "He never said much about his past and never mentioned Putin but he told me how lucky I was to live in a democracy.

"Why would anyone want to kill a man who was no harm to anyone? Nothing could prepare us for the knock at the door at 3am and seeing police milling about in protective suits."

Glushkov had a heart condition and a recent leg operation but seemed to be recovering well.

14 A blue tent obscured the entrance to the terraced house in New Malden, Surrey, on Monday, as police kept watch Credit: PA:Press Association

14 Cops were seen taking bags of evidence from the home where his daughter found him dead Credit: Jamie Lorriman

It comes soon after ex-Russian double agent Sergei Skripal and daughter Yulia, 33, were poisoned using a nerve agent developed in Russia.

Police are probing who targeted them, with Mrs May pointing the finger at Russia and giving Vladimir Putin a deadline to explain his country's involvement.

There is no suggestion the Salisbury poisoning was linked to that of Glushkov, 68, whose home has been taken over by forensics teams investigating his death.

Russian newspaper Kommersant, owned by Arsenal shareholder Alisher Usmanov, reported there were "traces of strangulation on his neck".

PM Theresa May confirms that Russia is 'highly likely' to have carried out the attack on former spy Sergei Skripal in Salisbury using military-grade nerve agent

14 Nikolai Glushkov, left, with Boris Berezovsky, centre Credit: east2west

Home Secretary Amber Rudd linked his death to that of his close friend - Russian oligarch and Putin critic Boris Berezovsky - who was also found dead in his London home in 2013.

Berezovsky's son-in-law Yegor Shuppe today branded Glushkov's death suspicious, telling the Daily Mail: "He did not have a sickness to die from. We helped him get good surgery, I often visited him."

One of Berezovsky's closest friends, Alexander Goldfarb, also said it seemed fishy, adding: "This looks very suspicious because of the recent attack on double agent Skripal."

His neighbours said Glushkov lived a reclusive life at his home in New Malden, where he lived with his dog - but had a passion for British democracy and champagne.

His daughter, who found his body, would visit regularly with her husband but he did not have much contact with the outside world, they claim.

An unnamed woman said the former Aeroflot boss suffered from medical problems, adding: "He had a very bad leg and recently had a big operation.

14 Neighbours said Glushkov lived a reclusive life at his home in New Malden Credit: Dan Charity - The Sun

​Former ​Russian ​deputy director of Aeroflot Nikolai Glushkov found dead at ​his home​ in New Malden​

14 His daughter, who found his body, would visit him regularly, neighbours claimed Credit: Dan Charity - The Sun

"He was in a lot of pain with it. He told me he had heart problems too, he used to go to Kingston Hospital and St George's in Tooting."

The woman, who said she had dinner with him when he first moved in four years ago, alluded to his anti-Putin leanings.

"I was round for dinner with him when he first moved in and he mentioned to me that we should 'appreciate democracy' more," she said.

"I never knew what his job was, I knew he did not want much. He was such a nice fellow, dinner was just the two of us."

A Met Police spokesperson said: "Whilst we believe we know the identity of the deceased, formal identification is yet to take place. A post-mortem examination will be held in due course.

"The death is currently being treated as an unexplained. If there is a change in the status of the investigation, an update will be provided.

14 Sergey and Yulia Skripal were poisoned in Salisbury

"At this stage the Met Police Counter Terrorism Command is leading the investigation as a precaution because of associations that the man is believed to have had."

A number of blue forensic tents were erected outside Glushkov's home overnight, with officers pouring over the scene.

His body was found hours after the Prime Minister gave Putin until midnight to explain Russia's involvement in the Skripal poisoning in Salisbury.

The British government is reported to be considering a range of sanctions against Putin.

But the Russian Embassy responded by saying: "Any threat to take 'punitive' measures against Russia will meet with a response. The British side should be aware of that."

Police and MI5 are now expected to investigate 14 deaths with possible links to Russia.

14 Police had been called to Glushkov's home in Kingston last night Credit: Twitter/Radio Jackie

14 Police said they were treating his death as 'unexplained' Credit: Radio Jackie

14 Police said that they were investigating Glushkov's death as a precaution Credit: Radio Jackie

Home Secretary Amber Rudd confirmed that security services were investigating, saying the UK "takes seriously any suggestion a foreign state has engaged in murder on UK soil".

And Foreign Secretary Boris Johnson said it was "highly likely" Russia was behind Skripal's poisoning and that it was an example of "further reckless behaviour with threatens the international community".

A Foreign Office statement added: "If this was a direct act by the Russian state then it would not simply be a threat to the UK, but a clear violation of the chemical weapons convention."

It said it would also be a "breach of international law and a threat to those who abide by the rules-based international order as a whole".

WHO WAS GLUSHKOV? Nikolai Glushkov was once one of the most powerful businessmen in Russia and instrumental in Vladimir Putin's rise to power before falling foul of the regime. The 68-year-old former deputy director of Russian state airline Aeroflot spent five years in jail due to money laundering and fraud. He was freed in 2004, eventually being granted political asylum in the UK. Glushkov was a close friend of the late oligarch Boris Berezovsky, an outspoken Putin critic who was also convicted of having defrauded Aeroflot in the 1990s. He gave evidence at a 2011 court case brought by Berezovsky against Roman Abramovich. After Berzovsky's death in 2013 Glushkov was vocal about his disbelief it was a suicide. He claimed it was a politically motivated death and alleged that Berezovsky and Alexander Litvenienko had been on a hit-list. In 2017 was sentenced in absentia to eight years in prison in a case of $122million embezzlement from the airline - he was ordered to pay the entire sum back. He has two grown up children, Natasha and Dima, and an ex-wife who lives in Moscow.

14 Glushkov had reportedly been suffering from a rare blood disease Credit: AP:Associated Press

Amber Rudd in Salisbury as police call in military to help investigate nerve agent attack on ex-Russian spy Sergei Skripal

Berezovsky had been found dead in 2013 in an apparent suicide but an inquest into his death recorded an open verdict.

Speaking to The Guardian in 2013, Glushkov said: "I will never believe in the natural death of Boris Berezovsky."

He also added that he feared he was on a hit list, saying: "You have the deaths of Boris and Badri over a short period of time.

"Too many bodies are happening. I would say this is a little bit too much. I don't see anyone left on it apart from me."

GLUSHKOV ON PUTIN'S RUSSIA: In his own words On Berezovsky in 2013: "You have the deaths of Boris and Badri over a short period of time. Too many bodies are happening. I would say this is a little bit too much." On Berezovsky suicide theory: "Boris was strangled. Either he did it himself or with the help of someone. [But] I don't believe it was suicide." About assassination hitlist: "I don't see anyone left on it apart from me."

14 Glushkov was the former first deputy director general of Aeroflot Credit: PA:Press Association

Archive video of radiation experts and cops at estate of exiled Russian tycoon Boris Berezovsky following his death

His friend Berezovsky was once a powerful friend of Putin, but fled to London in 2000 after falling out with the Russian President.

Glushkov lived in the UK, in a home in Kingston, South West London, after being granted political asylum in the country in 2010.

A Russian radio station reported that Glushkov had been suffering from a rare blood disease hemochromatosis, which causes your body to absorb too much iron from your food.

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He was tried in absentia in Moscow, sentenced to eight years behind bars over allegations of stealing $123m from Aeroflot.

Sources say there are now more Russian agents in London than during the Cold War — many posing as businessmen in posh flats in Mayfair and Knightsbridge.

The most recent poisoning in Salisbury has chilling echoes of the murder of Alexander Litvinenko in 2006 — and the notorious poison-tipped umbrella hit on Soviet defector Georgi Markov in 1978.

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