Another Novichok nerve agent has struck the U.K. recently, claiming one life and leaving another in critical condition in the hospital. Dawn Sturgess has tragically died, and Charlie Rowley remains in the hospital. Sturgess, 44, was a mother of three.

Last Saturday, Rowley and Sturgess of Amesbury, England were transported to the hospital after being found unconscious. After ruling out drug use or other more usual crimes, and after further testing, the National Counter Terrorism Policing Network were brought in to head up the investigation. It was later confirmed that Novichok was used in this attack.

Authorities are currently searching through the paths taken by Rowley and Sturgess to try to determine the origin of exposure.

Amesbury is under a 20 minute drive from Salisbury, where Sergei and Yulia Skripal were poisoned in March.

The Metropolitan police claims that neither Rowley or Sturgess have any history or connection that would clearly make them out to be targets. It is possible that they came across the stash of the nerve agent — if someone (like a Russian agent) were to carry out the Skripal attack, it would be unlikely that they would conduct such an operation with the bare minimum amount of Novichok to get the job done. For example, an assassin with a gun is going to carry more than one round. However, those extra rounds must be disposed of after the job is finished, and it’s possible that these two have come across the disposed Novichok. Another possibility is that they came across some leak or contaminated object from where the agent is being stored, however this is less likely since Novichok’s two primary elements must be mixed before it becomes deadly. There would be little reason to store it after it has been mixed, unless it was to be used.

Still, all of this is conjecture and the investigation continues, no doubt there will be an international outcry now that Sturgess has died. Further analysis by authorities may uncover clearer origins of this most recent exposure.

A police officer was also believed to have been exposed to a Novichok agent, but has since been cleared.

What does Russia’s ‘Novichok’ do to the body?