Double agent may have come in contact with nerve toxin on front door: UK police

British police said on Wednesday that former Russian double agent Sergei Skripal and his daughter, poisoned by a nerve toxin in an attack which Britain has blamed on Moscow, may have been exposed to the substance at the front door of their home.

“Specialists have identified the highest concentration of the nerve agent, to-date, as being on the front door of the address,” a statement by Scotland Yard said.

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“At this point in our investigation, we believe the Skripals first came into contact with the nerve agent from their front door,” Dean Haydon, head of the Metropolitan Police’s Counter Terrorism Command, was quoted as saying on the police website.

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“We are therefore focusing much of our efforts in and around their address.”

Allegations by London that the attack on 66-year-old Skripal, a former GRU military intelligence officer who betrayed scores of Russian agents to Britain, was the work of Moscow have been denied by Russia.

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But the affair has plunged Moscow’s relations with the West to a new post-Cold War low with Western governments, including the United States and Britain expelling scores of Russian diplomats.

Moscow has threatened to take retaliatory action.

Skripal and his 33-year-old daughter Yulia have been in a critical condition since being found unconscious on a public bench in the English city of Salisbury on March 4 and a British judge has said they may have suffered permanent brain damage.