A man fighting for his life in hospital after being exposed to an unknown substance in Salisbury, Wiltshire, is a spy who was convicted in Russia of passing state secrets to Britain.
Sergei Skripal, a former colonel in Russian military intelligence, was one of two people rushed to hospital on Sunday after collapsing at a shopping centre, both the Press Association and Reuters has reported.
The BBC also named Skripal as the man who was found along with a woman in her 30s, believed to be known to him, on a bench near the Maltings shopping centre shortly after 4pm.
“The pair, who we believe are known to each other, did not have any visible injuries and were taken to Salisbury District Hospital,” said Wiltshire Police temporary assistant chief constable Craig Holden.
“They are currently being treated for suspected exposure to an unknown substance.
“Both are currently in a critical condition in intensive care.”
Police said they were not currently treating the matter as a counter terrorism incident, but that the force will “continue to review this position”.
Zizi restaurant in Salisbury has been closed “as a precaution” in connection with the incident, Wiltshire Police said on Monday night.
Officers in regular uniforms and plain clothes spoke to staff inside and worked in tents in the area the pair were found.
Skripal was convicted in Russia in 2006 on charges of espionage for Britain’s MI6 intelligence agency.
The 66-year-old was sentenced to a 13-year prison term before he was pardoned in 2010 as part of a spy swap with the United States.
Police said it is not yet clear whether a crime has taken place, with the substance involved yet to be identified. An investigation has been launched.
“The focus at this moment in time is trying to establish what has caused these people to become critically ill, and we are working with partners to prioritise this diagnosis and ensure that they receive the most appropriate and timely treatment,” Holden added.
“A major incident has been declared today and a multi-agency response has been co-ordinated.”
Since finding refuge in Britain, Skripal kept largely out of the spotlight until he was seen making strange movements on a bench in Wiltshire on Sunday.
Witness Freya Church told the BBC: “On the bench there was a couple, an older guy and a younger girl. She was sort of leant-in on him, it looked like she’d passed out maybe. He was doing some strange hand movements, looking up to the sky.
“They looked so out of it that I thought even if I did step in I wasn’t sure how I could help, so I just left them. But it looked like they’d been taking something quite strong.”
Asked for a comment on the story, a spokesman for the Russian embassy said: “Neither relatives nor legal representatives of the said person, nor the British authorities have addressed the embassy in this regard.”
A number of sites around the city - including the scene where the pair were found - have been cordoned off by police in relation to the incident.
Relations between Britain and Russia have been strained since the murder of ex-KGB agent Alexander Litvinenko with radioactive polonium-210 in London in 2006, a killing which a British inquiry said was probably approved by President Vladimir Putin.
The Kremlin has repeatedly denied any involvement in the killing.
Litvinenko, 43, an outspoken critic of Putin who fled Russia for Britain six years to the day before he was poisoned, died after drinking green tea laced with the rare and very potent radioactive isotope at London’s Millennium Hotel.
Garry Kasparov, a former world chess champion and critic of Putin, was among those who drew comparisons with the death of Litvinenko.
But Igor Sutyagin, who was part of the same swap deal as Skripal and is now a research fellow at RUSI, urged caution.
He told the Associated Press: “There are lots of former security officers that deserted to the West. It is necessary to balance this information.”
Skripal, who was arrested in 2004 by Russia’s Federal Security Service (FSB) on suspicion of betraying dozens of Russian agents to British intelligence, was sentenced to 13 years in prison in 2006.
But he was later pardoned in 2010 by then-President Dmitry Medvedev as part of a spy swap to bring 10 Russian agents held in the United States back to Moscow.
The swap, one of the biggest since the Cold War ended in 1991, took place on the tarmac of Vienna airport where a Russian and a US jet parked side by side before the agents were exchanged.
One of the Russian spies exchanged for Skripal was Anna Chapman, who was greeted as a hero by the Kremlin. She was one of 10 spies who tried to blend in to American society in an apparent bid to get close to power brokers and learn secrets. They were arrested by the FBI in 2010.
Putin, himself a former KGB officer, sang patriotic songs with the returned spies.
It took some time for British doctors to discern the cause of Litvinenko’s illness.
While the incident in Salisbury is shrouded in mystery, it comes at a time of major tension in UK-Russian relations.
A report from the Commons Foreign Affairs committee last year describing the relationship between the two countries as being at “its most strained point since the end of the Cold War”.
And in evidence to the Commons Intelligence and Security Committee, MI6 described the Russian state as “formidable adversaries”.
Meanwhile, Salisbury District Hospital closed the doors of its accident and emergency department this morning after declaring a major incident involving a “small number of casualties”.
Patients were warned not to come to A&E unless dealing with an “extremely urgent” situation, with ambulances and fire engines were pictured at the scene as part of a “multi-agency response”.
However, investigators do not believe the incident poses a risk to the wider public and patients have been advised to attend scheduled appointments at the hospital unless told otherwise.
A Public Health England (PHE) spokesman said: “Based on the limited information available there doesn’t appear to be any further immediate risk to public health.
“PHE understands that those exposed to the substances have been decontaminated, as is standard practice in situations like this.”
Anyone with information about the incident should contact Wiltshire Police immediately via 999.