An MP admits he is "sceptical" about the original verdict on a helicopter crash which killed a Sunderland millionaire with Russian links.
Speaking in the aftermath of the Salisbury spy poisoning mystery, Sir Christopher Chope also claims the "the best assassins are the ones who cover their tracks" and that Russia is "very good at destroying their enemies".
Pilot Max Radford, 34, was also killed with an inquest jury later returning accidental verdicts on their deaths after hearing how the weather had deteriorated as the pair approached the end of their journey from London.
All involve the deaths in this country of Russian exiles or British citizens with links to the Eastern European super power. Foul play is so far ruled out in each instance.
In the case of former Bede Grammar School pupil and Red House resident Mr Curtis, who was 45 when he died, his London legal firm had started to work with wealthy Russians seeking to buy property in the English capital.
The solicitor's own fortunes blossomed to the extent that he was able to buy 19th-Century Pennsylvania Castle, near Portland, Dorset, although the Bournemouth inquest heard evidence from his family that the married dad had started to fear for his safety by the beginning of 2004.
Speaking about the Dorset helicopter crash, Conservative MP Sir Christopher claimed: "I was always sceptical about the official verdict on it but looking at these things, the best assassins are the ones who cover their tracks.”
He said Russia was “very good at destroying their enemies” and added: "Whether it could be the state or mafia groups or whoever, how can we prove it if you haven’t got the evidence?”
Home Secretary Amber Rudd last week said M15 and the police would shortly re-examine the 14 previous cases to "satisfy myself that the allegations are nothing more than that".
Mr Skripal and his daughter are still in a coma more than a fortnight after they were discovered on a bench in Salisbury on March 4.
Russia are strongly suspected by the British Government of committing the attack although Moscow denies any involvement.