A woman who died after being exposed to the nerve agent Novichok in Wiltshire is believed to have had a "high dose" of the substance, police have said.
Forty-four-year-old Dawn Sturgess passed away in hospital on Sunday after falling ill on June 30 in Amesbury. Her partner Charlie Rowley remains critically ill.
On Monday the Head of Scotland Yard's Counter-terrorism Policing, Assistant Commissioner Neil Basu, said while a possible link is one line of inquiry, they cannot yet be certain:
"The investigation is being led by detectives from the UK's counter-terrorism policing network and they are unable to say at this moment whether or not the nerve agent found in this incident is linked to the attack on Sergei and Yulia Skripal.
However, this remains our main line of inquiry. Their investigation must be led by the evidence available and the facts alone. Our focus and priority at this time is to identify and locate any container that we believe may be the source of the contamination."
The death of Dawn Sturgess is the subject of a murder inquiry and police are awaiting the results of a post-mortem examination.