Police in the UK say they have 'briefly spoken' to a man exposed to novichok, as the search continues for a container believed to have held the nerve agent.
45-year-old Charlie Rowley has regained conscious after falling ill over the weekend, with doctors saying his condition remains 'critical but stable'.
Mr Rowley's partner - 44-year-old Dawn Strugess - died on Sunday after exposure to novichok.
A number of sites in the towns of Amesbury and Salisbury are being examined as police work to discover how exactly the couple came in contact with the nerve agent.
Met Police said in a statement: "Officers from the investigation team have spoken briefly to Charlie and will be looking to further speak with him in the coming days as they continue to try and establish how he and Dawn came to be contaminated with the nerve agent.
"Any contact officers have with Charlie will be done in close consultation with the hospital and his doctors. We will not be providing further commentary around our contact with Charlie."
Container
Met Police Assistant Commissioner Neil Basu, meanwhile, explained: "We believe that Dawn and Charlie handled some kind of container which the nerve agent was in, and we're focusing our efforts on finding this container.
"Specialist officers are carrying out painstaking searches, but as I'm sure you will appreciate, this work is made all the more difficult as they have to carry out their activity in protective equipment, which significantly impacts the speed at which they can work.
"This, coupled with the extreme heat they have been working in, has proved extremely challenging for those carrying out this crucial work, but I know the officers are doing everything they possibly can to progress this as quickly as they can."
Earlier this year, novichok was used in the attempted murder of former Russian spy Sergei Skripal and his daughter Yulia in Salisbury.
The British government has repeatedly blamed Russia for that incident - claims Moscow has vehemently denied.
Police have said they 'cannot say with certainty' that the latest incident is linked with the poisoning of the Skripals - who were both discharged from hospital after weeks of treatment - but scientists are working to see if the nerve agents involved were from the same batch.
Met Police warn that it may "never be possible to establish such a definitive link" - but stress they will follow the evidence where it takes them.
Mr Basu added: "I would need a forensic link to be definitive, but this is a very rare substance banned by the international community and for there to be two separate distinct incidents in one, small English county is implausible to say the least."
