UK police have launched a murder investigation after the death of Russian businessman Nikolai Glushkov in south-west London.
Mr Glushkov was found dead at his home in the New Malden area of London on 12 March.
Police say Mr Glushkov, whose family has been informed, died from “compression to the neck”.
Police added there is, at this stage, no evidence linking the death to the incidents in Salisbury.
Detectives are retaining an open mind and are appealing for any information that will assist the investigation.
In particular, they are appealing for anyone who may have seen or heard anything suspicious at or near his home in Clarence Avenue, New Malden between Sunday 11 March and Monday 12 March to contact them.
Mr Glushkov is the former deputy director of Russian state airline Aeroflot.
He was jailed in 1999 for five years after being charged with money laundering and fraud.
After being given a suspended sentence for another count of fraud in 2006, he fled to the UK to seek political asylum and became a critic of Russian President Vladimir Putin.
Mr Glushkov also had a close friendship with fellow Russian businessman Boris Berezovsky, who came to the UK in 1999 after falling out with Mr Putin.
Mr Berezovsky was found hanged in the bathroom of his Berkshire home in 2013 and an inquest recorded an open verdict.
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