Sergei Skripal was poisoned with nerve agent outside his front door, police say

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Military personnel wearing protective suits remove a police car and other vehicles from a public car park as they continue investigations into the poisoning of Sergei Skripal on March 11, 2018 in Salisbury, England.

Sergei Skripal and his daughter Yulia were poisoned with nerve agent outside of his front door, police have said.

In a statement released on Wednesday evening, Metropolitan Police investigating the case have said that the former Russian spy is believed to have come into contact with the lethal poison outside of his house in Salisbury, England. It remains unclear exactly how they came into contact with them, or how it came to be there.

The United Kingdom has blamed Russia for the chemical weapons attack, a charge Russia has denied. Britain's international allies have rallied around it in recent days, expelling dozens of Russian diplomats from their postings around the world.

"At this point in our investigation, we believe the Skripals first came into contact with the nerve agent from their front door," Deputy Assistant Commissioner Dean Haydon, Senior National Coordinator for Counter Terrorism Policing said. "We are therefore focusing much of our efforts in and around their address. Those living in the Skripals' neighbourhood can expect to see officers carrying out searches as part of this but I want to reassure them that the risk remains low and our searches are precautionary."

There have previously been multiple theories swirling about how the Skripals were poisoned - including that the nerve agent had been hidden in Yulia Skripal's luggage before she travelled back from Russia, that it was smeared on a car door, or that it was hidden in their food.

Yulia and Sergei Skripal remain critically ill in comas in hospital.

This story is developing...