Counter-terror police investigate suspected poisoning of Russian spy

British counterterrorism police are now leading the investigation into the suspected poisoning of a former Russian spy, showing that UK authorities are treating the case with increasing seriousness.

A spokesman for the London Metropolitan Police confirmed the news to Business Insider, citing the "unusual circumstances" of the incident.

"The Counter Terrorism Policing network will lead the investigation as it has the specialist expertise to do so," Scotland Yard said. "It has not been declared a terrorist incident and at this stage we are keeping an open mind as to what happened."

Sergei Skripal, 66, and his daughter Yulia, 33, were found collapsed on a bench at a shopping center in Salisbury, south England, on March 4, 2018. Both remain in a critical condition at a nearby hospital. An update on the substance they were both exposed to is expected on March 6, 2018.

Mark Rowley, assistant commissioner of London's Metropolitan Police, said, "the focus at this time is to establish what has caused these people to become critically ill."

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"We would like to reassure members of the public that this incident is being taken extremely seriously and we currently do not believe there is any risk to the wider public."

Earlier, he told the BBC's Today radio program, "if you look back at other cases like [Alexander] Litvinenko, if necessary, we will bring that investigation into the counterterrorism network."

Alexander Litvinenko was a former KGB spy who was poisoned in London in 2006. He accused Russian President Vladimir Putin of ordering his murder on his deathbed.

Meanwhile, Kremlin spokesman Dmitry Peskov called the incident "a tragic situation," but denied knowing any information about the case, Reuters reported. He added that Russia would be ready to cooperate with the investigation if asked.

When asked to respond to media speculation in the UK that Russia had poisoned Skripal, Peskov said, "it didn't take them long."

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Skripal worked for the Russian military intelligence and foreign ministry until 2003, before being sentenced to 13 years in jail in 2006, Sky News reported.

He confessed that he had been recruited by British intelligence in 1995, and passed the identities of Russian agents in Europe for around $100,000.

He was granted asylum in Britain after being pardoned by Russia in a 2010 "spy swap" deal with the US, under which 10 Russian spies arrested by the FBI were released.