The police officer who was poisoned by a nerve agent in an attack on a former Russian spy has been named as Detective Sergeant Nick Bailey.
DS Bailey is seriously ill in hospital after being one of the first on the scene when Sergei Skripal, 66, and daughter Yulia, 33, were attacked in Salisbury, Wiltshire.
Home secretary Amber Rudd told the House of Commons his condition "remains serious but stable" and that he was "conscious, talking and engaging" on Thursday.
Wiltshire Police confirmed 21 people had received medical treatment in connection with the incident.
Mr Skripal and his daughter were found slumped on a bench in Salisbury town centre, having fallen into a "catatonic state" after eating out at a nearby Zizzi's restaurant.
Forensic scientists were seen bringing in equipment to scour the former double agent’s semi-detached home in a cul-de-sac, as hundreds of detectives and analysts worked on reconstructing their movements prior to the attack.
However the Russian Embassy said it was "completely untrue" to suggest the country's special services were involved and criticised Mr Johnson for speaking "in such a manner as if the investigation was already over".
Mr Skripal was convicted in 2006 of passing state secrets to MI6 before being given refuge in the UK as part of a spy swap.
Their relatives told the BBC Russian Service that the former spy believed the Russia special services would come after him at any time.
An anonymous relative was quoted as saying “he knew it would end badly and that he would not be left alone”.
The deaths of his wife and son had died in the last ten years are reportedly being considered as part of the investigation.
The Met Police said the case was being treated as attempted murder and Mr Skripal and his daughter were deliberately targeted.
He was described by neighbours and acquaintances as a quiet, kind and “grandfatherly” man, which is at odds with reports he remained in contact with the security forces during his time in Salisbury.
They described him as educated, well-read and widely travelled but with few friends. He rarely mentioned his past and seemed unaware of an imminent threat to his life.
His weekly routine appears to have included regular visits to Taste of the East, a Polish deli where he would buy meats, and visits to the Railway Social Club.
Ebru Ozturk, 41, owner of Bargain Stop convenience store, about half a mile from Mr Skripal’s house, sold him milk and scratchcards last week.
She said: “I felt he was a professional with the government but he never said so. You could tell he had done some important jobs but he said he had retired.
"We had talked about the different countries he’d been to but nothing about the military. He told me he was from the Ukraine but had lived in Russia. He told me he didn’t have many connections there.”
A former Kremlin official has claimed that the ex-double agent had remained in “regular contact with the Russian embassy”.
Valery Morozov, who was exiled to the UK and was an associate of Mr Skripal, said he believed that the former spy was still working in cyber-security.
He also claimed that he chose to distance himself from Mr Skripal because he was keeping “dangerous” company.
Mr Morozov told Channel 4 News: “Every month he was going to the embassy to meet military intelligence officers.”
It is also claimed that Mr Skripal gave regular lectures to the British security services on the inside workings of the Russian security agency.
The investigation continues.