Detectives have launched a murder inquiry after a woman who was exposed to the nerve agent Novichok in Amesbury, Wiltshire, died in hospital this evening, Sunday, 8 July.



She has been formally identified as 44-year-old Dawn Sturgess, from Durrington. Her family has been informed and is receiving support from specially trained family liaison officers.



A post-mortem will be scheduled to take place in due course.



A 45-year-old man who was also taken ill following exposure to the nerve agent remains critically ill in hospital.



The investigation is being led by detectives from the Counter Terrorism Policing Network and around 100 detectives are working round the clock alongside colleagues from Wiltshire police.



Assistant Commissioner Neil Basu, the head of UK Counter Terrorism policing said: "This is shocking and tragic news. Dawn leaves behind her family, including three children, and our thoughts and prayers are with them at this extremely difficult time.



"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.



"This terrible news has only served to strengthen our resolve to identify and bring to justice the person or persons responsible for what I can only describe as an outrageous, reckless and barbaric act.



"Detectives will continue with their painstaking and meticulous work to gather all the available evidence so that we can understand how two citizens came to be exposed with such a deadly substance that tragically cost Dawn her life.



"Dawn's family has asked the media to kindly respect their privacy at this difficult time."



At approximately 10:15hrs on Saturday, 30 June, the South West Ambulance Service was called to a residential address in Amesbury, where Ms Sturgess collapsed. She was subsequently taken hospital.



At around 15:30hrs on the same day, the ambulance service was called back to the same address after the 45-year-old man had fallen ill. He was also taken to hospital and Wiltshire police informed.



The Defence Science and Technology Laboratory at Porton Down confirmed to us on Wednesday, 4 July that Ms Sturgess and her friend had been exposed to Novichok.



No-one else has presented with the same symptoms linked to this incident.



Further tests of samples from Dawn and the man showed that they were exposed to the nerve agent after touching a contaminated item with their hands.



Detectives are working as quickly and as diligently as possible to identify the source of the contamination, but this has not been established at this time.



There is no evidence that they visited any of the sites that were decontaminated following the attempted murders of Sergei and Yulia Skripal in March this year. We are not in a position to say whether the nerve agent was from the same batch that the Skripals were exposed to.



The investigation into the attempted murders of the Skripals is ongoing as detectives continue to assess all the evidence available.



The possibility that the two investigations might be linked is clearly a key line of inquiry for police. However, it is important that the investigation is led by the evidence available and the facts alone.



We are keen to hear from anyone who may have information that could assist with this investigation and would urge anyone to help to contact police by calling 0800 789 321.