Simon Jenkins asks where the evidence is to support the allegation that the Russian state was responsible for the poisonings in Wiltshire (Why wait for evidence when you can just accuse Russia?, 6 July) Perhaps it is worth reiterating some facts.

We know that Russia invented and developed the nerve agent used in Salisbury. We know that a Russian double agent was the target. We know that Putin has a track record of ruthlessly eliminating his enemies.

Additionally, declassified intelligence alleges that Russia has investigated various methods of delivering nerve agents, “including by application to door handles”, and that Sergei and Yulia Skripal’s email accounts have been targeted by the Russian state since at least 2013. To suggest there is any ambiguity, therefore, is farcical.

Jenkins asks why Putin would do this now. It would be more pertinent to ask why he wouldn’t. After 18 years in power, Putin believes he can bully and intimidate his way out of any problem. It is up to our government and allies to prove him wrong.

Tom Davies

Churt, Surrey

• Once again the government is making unsubstantiated accusations against Russia (Javid: Moscow is using Britain as dumping ground for poison, 6 July). Consider the facts:

1. The UK has been able to provide no evidence of Russian state interference.

2. Sergei Skripal was known to have worked as a double agent and also had contacts in the murky Russian expat world.

3. In the light of what we know about Russian secret operations, can we really believe a trained agent made such a bodged attempt to kill Skripal and then just threw away “an item” willy-nilly to be found and then assist forensic teams?

This whole saga points to an amateur revenge attack on Skripal or devious shenanigans by MI6 to bolster the concept of Russia as the enemy. Our arms industry always needs a bogeyman

Jane Ghosh

Bristol

• Simon Jenkins’ air of reasonableness is compromised by his omission of any reference to the Litvinenko assassination. The use of polonium and more recently novichok in Britain have the same hallmarks of deadliness and ineptitude: as much Keystone Cops as FSB. Just as the killers of Litvinenko left a radioactive trail round London, the latest would-be assassins left novichok round Salisbury and wherever the latest unfortunate victims made contact with the substance. And isn’t it more likely that the novichok that poisoned them was just recklessly abandoned rather than “planted”?

Mark Haworth-Booth

Swimbridge, Devon

• No, Simon Jenkins, you are not the only person alive with no clue as to who has poisoned four people in Wiltshire. When politicians and the media immediately blamed Russia over the poisoning of the Skripals, it was Jeremy Corbyn who advised caution, saying the investigation of the crime should follow the due process of the law. He was immediately pilloried in the press and labelled a stooge of Putin. He was a brave man to stick his head above the parapet. Now, perhaps, others may also start to question the motives and origins behind these attacks.

Pat Brockbank

Winterbourne, Gloucestershire

• So far as we have been informed, novichok was a nerve agent produced in the Soviet Union. The USSR ceased to exist over quarter of a century ago, and as you have previously said (Was Russia’s stockpile of chemical weapons completely destroyed?, 16 March), stocks of such agents were poorly guarded for several years, permitting the opportunity for theft.

If our politicians really do want to get to the bottom of the Salisbury/Amesbury incidents, they’d surely do better to set up a joint inquiry as suggested by Russia, to find out, for example, if anyone had a grudge against the Skripals, rather than issuing instant denunciations.

Robin Milner-Gulland

Washington, West Sussex

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