Russian ex-spy and daughter poisoned with nerve agent, police say

British police said Wednesday that they believe a Russian former spy and his daughter were poisoned with a nerve agent.

Metropolitan Police counterterrorism chief Mark Rowley said the attack on Sergei Skripal, 66, and his daughter Yulia, 33, on Sunday is being treated as attempted murder.

He said police think the pair were specifically targeted. They are both in critical condition in intensive care, London's Metropolitan Police said. A police officer who initially responded to the situation is also in intensive care after being exposed to the substance.

Metropolitan Police said scientific tests by government experts have identified the specific nerve agent used, which will help identify the source. "But at this stage in a fast-paced ongoing investigation we will not comment further," police said in a statement.

Sergei Skripal, an ex-Russian military intelligence colonel, was found unconscious Sunday with his daughter Yulia Skripal on a bench at a shopping center in an English town.

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Police initially said the pair had been exposed to an "unknown substance" while shopping in Salisbury, a small city about 90 miles west of London.

"Due to the unusual circumstances, it has been decided that the Counter Terrorism Policing network will lead the investigation," police said Tuesday. "It has not been declared a terrorist incident and at this stage we are keeping an open mind as to what happened."

The incident is reminiscent of the 2006 poisoning death of another former Russian agent, Alexander Litvinenko, after he was exposed to a rare radioactive isotope, polonium-210.

Litvinenko’s widow, Marina, wrote Wednesday in the Times of London that her husband’s case made clear that Britain’s emergency services need to act quickly when “someone suddenly falls mysteriously ill.”

Who is Sergei Skripal?

Sergei Skripal is a former Russian double agent convicted of passing identities of Russian agents working undercover in Europe to MI6, the British foreign intelligence service.

Russia jailed Skripal for treason in 2006 after he confessed to working for British intelligence and supplying information about Russian agents. Skripal admitted selling the names, addresses and code names of dozens of Russian agents to MI6 over 10 years.

Skripal's motives may have been financial: Russian prosecutors said MI6 paid him $100,000 for the information, the Guardian reported.

Russia freed him in 2010 as part of a U.S.-Russian spy swap and he moved to Britain.

Skripal worked in Russian military intelligence until at least 1999. He then transferred to the foreign affairs ministry where he worked until 2003, according to the Independent. After 2003, he went into business.

Skripal's daughter worked for Nike in Russia until around 2010, when according to her social media she moved to London, and was employed at the Holiday Inn in Southampton over the summer of 2014, the Telegraph reported. Her social media profile indicates she now works for Pepsico in Moscow, according to the Telegraph.

What was he doing in Salisbury?

For more than five years he has lived in a modern red-brick home close to the city center, according to the Guardian.

He "seemed like a nice chap. When he moved in he invited us all over for a housewarming party – I imagine he invited the whole street,” neighbor James Puttock told the Guardian.

His daughter visited him frequently, the Telegraph reported.

What happened to the rest of his family?

Skripal’s son, 43, died last year on a visit to St. Petersburg with his girlfriend, the BBC reported. His wife, Liudmila, also died in 2012 at age 59 of endometrial cancer.