A couple rushed to hospital by paramedics dressed in hazmat suits were poisoned by the same nerve agent used against former Russian spy Sergei Skripal, police confirmed.

Dawn Sturgess, 44, and her partner Charlie Rowley, 45, are fighting for life after they were exposed to the deadly Novichok substance in Amesbury on Saturday.

They were exposed just 300 yards from where Mr Skripal and his daughter Yulia ate on the day they were poisoned four months ago, and it was feared this could be leftover toxin from then.

Confirmation of the poisoning came hours after dramatic video emerged of one of the victims being loaded into an ambulance by a paramedic wearing hazmat gear.

Rowley was lying on his back in a stretcher as the paramedic in a white protective suit pushed it inside as two police officers watched on.

Sturgess lives in a homeless shelter close to the Zizzi's restaurant in Salisbury where Russian spy Sergei Skirpal and his daughter Yulia were targeted four months ago.

Assistant Commissioner of Specialist Operations Neil Basu said blood samples were tested at the UK's Defence Science and Technology Laboratory at Porton Down and confirmed to be Novichok.

'Following the detailed analysis of these samples, we can confirm that the man and woman have been exposed to the nerve agent Novichok, which has been identified as the same nerve agent that contaminated both Yulia and Sergei Skripal,' he said.

'The latest update we have from the hospital is that both patients remain in a critical condition. Both are British nationals and are local to the area. Officers are still working to identify their next of kin.

'The priority for the investigation team now, is to establish how these two people have come into contact with this nerve agent.'