The Russian Foreign Ministry on Wednesday demanded London prove British spies did not poison a former double agent in England, saying in the absence of such proof it would regard the incident as an attempt on the lives of Russian citizens. They remain in a hospital in critical condition. They had no visible injuries, according to police. "The unique circumstances of this investigation means that officers are likely be in the area for several weeks and months".
Deputy assistant commissioner Dean Haydon, senior national coordinator for counter terrorism policing, said: "At this point in our investigation, we believe the Skripals first came into contact with the nerve agent from their front door".
Detectives have found traces of the nerve agent at other scenes in the past few weeks but at lower concentrations than at the home address, the Met Police said.
Officers are examining more than 5,000 hours of closed-circuit television and more than 1,350 seized items, police said.More news: LiAngelo Ball decides to enter National Basketball Association draft
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About 500 witnesses have been identified and hundreds of statements taken, police said.
Britain blames Russian Federation for the poisoning but Russian Federation denies any responsibility. Kremlin says open to summit with Trump The Kremlin says it is still open to asummit meeting with US President Donald Trump despite the fact that the US earlier this week ordered the expulsion of 60 Russian diplomats from the country.
In response to the poisoning, more than 150 Russian officials have been expelled from over 25 countries, and the United Kingdom government is considering further measures to punish Russian, including a ban on the City of London from selling Russian sovereign debt. Those countries include the United States, Canada, Australia and 18 European Union states.
The prime minister said on Wednesday that the government had evidence that Russian Federation had explored ways of exporting nerve agents over the past decade, most likely for the purposes of assassinations.