Residents of the homeless hostel in Salisbury where Sturgess lived, which was evacuated after the couple fell ill, expressed their devastation at the news of her death.
Defense Minister Gavin Williamson blamed Russian Federation for "committing an attack on British soil", speaking to MPs after an inter-ministerial meeting on the Cobra crisis.
On Sunday, police issued a statement saying there had been no evidence that either Rowley or Sturgess had been to any decontaminated sites from the nerve agent attack on Skripal and his daughter.
A Wiltshire Police spokesman said: "We have arranged the transportation of a vehicle from an address in Swindon this evening in relation to the on-going incident in Amesbury".
"However, if there is anyone who saw them or met with them who we haven't already spoken to, I would urge them to contact police on 0800 789 321".
Basu also said he did not believe there was much novichok in Salisbury - because the attackers would have been "foolish" to carry a large amount in.
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More than 100 police officers have been working to locate a small vial or other container thought to have held the nerve agent that sickened the two.
"This is a very rare substance banned by the global community and for there to be two separate, distinct incidents in one small English county is implausible to say the least", Basu added. Sturgess and Rowley were found at a house in Amesbury, 11 km (7 miles) away.
"The brutal reality, however, is that I can not offer you any such assurances or guarantees at this time". It is not known if he has been told that his girlfriend has died.
A member of the audience suggested that authorities had not been looking for the Novichok until the latest incident.
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The new findings come on the heels of prior studies which showed that supplements have few, if any, health benefits. Millions of Americans take multivitamins as a quick fix for the nutrients missing from their diets.
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Portugal made the last 16 of the tournament, in stark contrast to Italy, who failed to qualify for the first time since 1958. Its members will walk out at 22:00 local time on Sunday and remain on strike until 18:00 on the following Tuesday.
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Chris is located about 245 miles southeast of Halifax, Nova Scotia, and about 470 miles southwest of Cape Race, Newfoundland. On the forecast track, the center of Chris will pass over or near southeastern Newfoundland Thursday afternoon or evening.
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Adisak Wongsukchan told Al Jazeera he gave his 14-year-old son Nong Bew a big thumbs up when he first saw him in hospital. The Wild Boars football team which were stuck in Tham Luang Nang Non cave for 18 days after monsoon floods.