A former Russian spy has become critically ill after being exposed to an unknown substance, with parallels being drawn to the 2006 poisoning of former KGB and FSB man Alexander Litvinenko.
The BBC reports that 66-year-old Sergei Skripal was granted refuge in the UK following a "spy swap" between the US and Russia in 2010.
He was found unconscious in a shopping centre in Salisbury on Sunday alongside a 33-year-old woman, thought to be his daughter. Nearby restaurant Zizzi and The Bishop's Mill pub in The Maltings have been closed as a "precaution".
Wiltshire Police this morning confirmed that the pair were in critical condition in intensive care. "Our thoughts are with their families," the force said in a statement. They could not confirm how long the cordons would remain in place.
A "small number" of emergency services staff were taken to hospital for an assessment, and all but one have been released.
"The advice from Public Health England remains that, based on the evidence to date, currently there doesn't appear to be any immediate risk to public health," the statement added.
The incident has been likened to the 2006 polonium poisoning of Russian dissident Alexander Litvinenko in London. A public inquiry concluded that the killing of Litvinenko, an outspoken critic of Vladimir Putin, had "probably" been carried out with the approval of the Russian president.
His widow Marina told the Telegraph: “It looks similar to what happened to my husband but we need more information. We need to know the substance. Was it radioactive?”
And former world chess champion Garry Kasparov has weighed in, saying: "Not yet confirmed he was murdered, but after the UK's pathetic response to Litvinenko's assassination with polonium in London, why wouldn't Putin do it again?"
Skripal is a retired Russian military intelligence officer who was jailed for 13 years by Russia in 2006 for spying for Britain.
He was convicted of passing the identities of Russian intelligence agents working undercover in Europe to the UK's Secret Intelligence Service, MI6.
In 2010, Putin made it clear what would happen to those found guilty. "Traitors will kick the bucket, trust me,” he said at the time.
“These people betrayed their friends; their brothers in arms. Whatever they got in exchange — those 30 pieces of silver they were given — they will choke on them.”
There were many issues at stake: the annexation of Crimea, "repeatedly" violating the national airspace of a number of European countries, meddling in elections, hacking the Danish and German governments and spreading fake news. But one thing she didn't mention was poisoning of Russian nationals in foreign territory.
Buzzfeed last year revealed that there have been 14 cases where US agencies believe people have been assassinated in the UK by Russian security services or mafia groups - but foul play had been ruled out every time.
She was home secretary at the time of Sir Robert Owen's report into the Litvinenko case, damning it as a “blatant and unacceptable breach of international law”. At the time she announced the government would freeze the two suspects’ assets.
However, there was criticism - both at the time and subsequently - that these measures did not go far enough and let senior figures within Russia off the hook.