While officers are not fixing him, he is believed to be businessman Nikolai Glushkov, who was top of a list of “fugitives from justice” published by the Russian embassy which accused him of committing “severe financial offences”.
Scotland Yard pronounced anti-terror police were questioning his death “as a prevision since of associations that the man is believed to have had”.
But it pronounced there was “no justification to advise a couple to the occurrence in Salisbury”, adding that the death was being treated as “unexplained”.
One of Mr Glushkov’s friends was late Russian oligarch Boris Berezovsky, who fled to London in 2000 following a quarrel with Vladimir Putin.
Mr Glushkov, a former emissary executive of the Russian airline Aeroflot, had also worked for Mr Berezovsky’s LogoVAZ automobile company.
After Mr Berezovsky was found hanged in the lavatory of his Berkshire home in Mar 2013, Mr Glushkov told The Guardian he would “never believe” his crony took his own life.
An inquisition into Mr Berezovsky’s death recorded an open verdict.
Mr Berezovsky was also a crony of Russian anarchist Alexander Litvinenko, who was tainted with hot polonium-210 in London in 2006.
Police and MI5 are approaching to inspect allegations that a series of deaths on UK soil, including the Berezovsky case, may be related to Russia.
Sky News’ home affairs correspondent, Mark White, pronounced Mr Glushkov’s home in New Malden, southwest London, was being treated as a crime scene. Officers were called by the London Ambulance Service at 10.46pm on Monday.
Local proprietor Tracy Broadfield pronounced the police participation was “very large”.
Neighbour Patricia Egan pronounced Mr Glushkov had lived there for several years, describing him as good prepared and “a lovely fellow”.
“His daughter used to call – she was in her 20s we think,” she added.
The physique was private at about 8.15pm on Tuesday and taken divided in a private ambulance.
Mr Glushkov was arrested in 1999 and put on hearing for allegedly embezzling $7m from Aeroflot, and condemned in 2004 to 3 years, 3 months in prison.
Russian media pronounced he was postulated domestic haven in Britain in 2010.
But his case was regenerated by a Moscow justice last year, which condemned him in absentia to eight years for allegedly embezzling some-more than $122m from Aeroflot.
The Russian embassy pronounced it had sought Mr Glushkov’s extradition in 2015 “for committing a series of serious financial offences on the domain of Russia”, but the British supervision refused.