"The 45-year-old man who fell ill with Dawn remains critically ill in hospital and our thoughts are with him and his family as well", he said in a statement. While Russia made a point past year of destroying its last remaining stockpiles of publicly declared chemical weapons, Reuters noted that it is "not believed to have ever declared Novichok or its ingredients to the Hague-based Organisation for the Prohibition of Chemical Weapons (OPCW)".
Assistant Commissioner Neil Basu, the head of UK Counter Terrorism policing said: "This is shocking and tragic news". May also said her "thoughts and condolences" go to Sturgess' family and loved ones.
Police opened a murder investigation after Sturgess died in hospital on Sunday at 8.26pm.
Britain has blamed Russian Federation for the Skripal poisonings - a charge Russian Federation denies.
"Our thoughts are also with the people of Salisbury and Amesbury and the Home Secretary will make a statement shortly including on the support we will continue to provide to the local community throughout this hard time".
Following the latest poisonings, Public Health England said the risk to the public remains low, but advised against picking up odd items like needles, syringes and unusual containers.
Police stress none of them are showing any signs of having been exposed to the nerve agent or feeling unwell.
Detectives are working to identify the source of the contamination, police said, but a source has not yet been established.
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Police said there were no indications that Crenshaw was under the influence of drugs or alcohol at the time of the incident. Jonathan Crenshaw was often seen on the streets of South Beach painting canvas with his brush between his toes.
The British couple, Sturgess and Rowley, were found on May 30 unconscious at a house in Amesbury, Wiltshire - about 10 miles from where Skipal and his daughter were poisoned.
Ms Sturgess, 44, died in hospital on Sunday evening after falling ill in Amesbury, Wiltshire, ten days ago.
The Kremlin has denied, as it did after attack on Skripal, any involvement with poisoning of Rowley and Sturgess, which it considers "deeply troubling", and called on British authorities not to incur "dirty political games" by relating Poisoning with case of Skripal.
The Porton Down laboratory near Salisbury confirmed on Wednesday that the victims had been exposed to novichok.
Following the death, there are growing fears of a wider risk to public health in the region but Public Health England stressed the risk to the general public "remains low".
A police sergeant involved in the investigation was hospitalised and released.
"We are not in a position to say whether the nerve agent was from the same batch that the Skripals were exposed to", the Met said, adding that the investigation into the attempted murders of the Skripals were ongoing.
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