Police are trying to determine how the bottle got to the house and whether the poison was from the same batch that sickened Sergei Skripal, 66, a former Russian spy, and his daughter Yulia, 33, in the city of Salisbury - about 10 miles from Amesbury - on March 4.
"Investigators believe they have identified the suspected perpetrators of the Novichok attack through CCTV and have cross-checked this with records of people who entered the country around that time".
It follows a USA report that investigators suspect that the attempted murder of Mr Skripal, 67, and his daughter, Yulia, 33, in Salisbury in March was carried out by Russian members of the...
A team from the Organisation for the Prohibition of Chemical Weapons (OPCW) was called in to independently verify that the nerve agent had fatally poisoned Dawn Sturgess and left her partner Charlie Rowley seriously ill. They were treated for exposure to the rare Soviet-era military-grade nerve agent Novichok and discharged separately from hospital several weeks later.
The Metropolitan Police, who are leading the investigation, declined to comment on the allegation. Last week, the watchdog was asked by the United Kingdom to deploy another team to determine the nature of the substance to which Sturgess and Rowley were exposed. "We are interested in the real results of the probe", he said, adding that he will try to organize a meeting with Britain's foreign secretary to discuss it.
The U.K. has blamed Russian Federation for the attack, a charge that the Kremlin has strongly denied.
Queen Elizabeth Gardens and other locations in Salisbury and nearby Amesbury were cordoned off last month after Mr Rowley, 45, and Ms Sturgess, 44, were exposed to the nerve agent.
They say that many of these could also be contaminated by Novichok.
Senior coroner David Ridley opened an inquest into the poisoning death of Sturgess Thursday, but said the cause of Sturgess' death won't be given until further tests are completed.