Sajid Javid has called on Russia to give a proper explanation for the Salisbury and Amesbury poisonings, accusing Moscow of using Britain as a “dumping ground for poison”.
The home secretary told MPs the “eyes of the world” were on the country, “not least because of the World Cup”, adding: “It is now time that the Russian state comes forward and explains exactly what has gone on.”
Mr Javid accused Moscow of trying to undermine UK and international security, pledging to “stand up to the actions that threaten our security”.
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He added: “It is completely unacceptable for our people to be either deliberate or accidental targets, or for our streets, our parks, our towns, to be dumping grounds for poison.”
The home secretary was speaking in the Commons in the wake of two people falling ill in Wiltshire after being exposed to the nerve agent novichok.
Dawn Sturgess and Charlie Rowley were taken ill in Amesbury and are fighting for their lives in hospital, with more than 100 counter-terrorism detectives now investigating.
They were taken ill around eight miles from Salisbury, where former Russian spy Sergei Skripal and his daughter Yulia were poisoned with novichok in March.
Britain has blamed this poisoning on Moscow, something Russia has furiously denied responsibility for.
Mr Javid told MPs it was the government’s “strong working assumption” that the Amesbury pair came into contact with the nerve agent in a different location to the sites involved in the original clean-up operation following the poisoning of the Skripals.
He said the risk to the public remained low, adding: “We have taken a very robust approach to decontamination and there is no evidence that either the man or the woman in hospital visited any of the places that were visited by the Skripals.”
One theory that is understood to be under investigation is that the pair may have inadvertently discovered a container, like a phial or syringe, used to transport the nerve agent used to attack Skripals.
Even the tiniest trace of the highly toxic nerve agent could account for their severe illness.
Mr Javid said he “cannot rule out” the possibility that the novichok found in Amesbury was from the same batch used in Salisbury.
“What we are absolutely clear on from Porton Down is that this is the exact same nerve agent from the novichok family of nerve agents, but the same type of nerve agent from that family that was used in the March attack,” he told the Commons.
“We cannot attribute this to the same batch at this point and scientists will be looking into that, I’m also told that may not even be possible because of a number factors, but we cannot rule out, of course, that it was from the same batch.”
Mr Javid also warned of a possible disinformation campaign from the Kremlin in the wake of the latest incident, saying: “We have already seen multiple explanations from state sponsored Russian media regarding this latest incident.
“We can anticipate further disinformation from the Kremlin as we saw following the Salisbury attack.”
Prime Minister Theresa May said the government will “continue to provide every support to the local community” and Salisbury is “very much open for business”.