Skripal, who was granted refuge in Britain as part of a 'spy swap' with fellow double agent Anna Chapman, is fighting for his life after being exposed to an unidentified chemical.

AN ex-Russian spy who is believed to have been poisoned in a UK shopping centre had contacted cops fearing for his life after the mysterious deaths of his wife and son.

Retired spy Colonel Sergei Skripal, 66, and a woman - believed to be his daughter - are both critically ill in a Wiltshire hospital after being found slumped in the Maltings shopping centre in Salisbury.

Police said the pair were exposed to an unidentified substance and have cordoned off a Zizzi restaurant nearby "as a precaution" which would suggest that one or both of the victims had dined there.

Recent reports said Skripal was fearing for his life after his wife died in a car crash shortly after arriving in the UK while his son also killed in a road accident in Russia.

Investigators were scrambling to identify the chemical used in the attack which has sparked fears of a Kremlin-backed hit on Skripal, who was jailed for treason in Russia and came to Britain in a 2010 spy swap.

The incident also has echoes of the 2006 killing of former KGB officer Alexander Litvinenko who was poisoned with radioactive polonium in London.

Emergency crews in protective suits decontaminated the scene where Skripal, who came to Britain in a spy swap involving flame-haired double agent Anna Chapman, was found.

• Sergei Skripal was born on June 23 1951.
• He was arrested in December 2004 after Russia accused him of passing on identifties of its spies onto the UK's Secret Intelligence Service MI6.
• It claimed Skripal had been paid the $100,000 (£72,270) for the information which he had been supplying since in 1990s.
• At the time he was serving in the Russian Ground Forces.
• Skripal was said to have passed secrets to MI6 through a James Bond-style fake rock hidden in Moscow park.
• Russian secret services exposed the rock in 2006, revealing how agents transmitted data to it via a hidden handheld device.
• He was found guilty of 'high treason in the form of espinoage' and sentenced to 13 years in prison.
• However he was released by Moscow in 2010 following a 'spy swap' deal made between the US and Russia.
• Among the trade-off was glamour spy Anna Chapman.
• He was nicknamed 'the spy with the Louis Vuitton bag' after pictures showed him carrying a bag at an airport en route to meeting his handlers.
• Skripal was then flown to the UK and granted refuge. After settling in Salisbury in a £350,000 semi-detatched house his wife Liudmila who died in 2012.

Skripal was taken to the city’s hospital by ambulance while his daughter was flown by air ambulance and their arrival sparked the shutdown of the hospital’s A&E department.

Police declared a major incident and quarantined key locations including the A&E department, where up to 12 people began vomiting.

As emergency crews cleared the substance left near the bench, others were called to decontaminate the hospital.

First reports suggested traces of the opiate fentanyl — a synthetic toxin many times stronger than heroin — had been detected at the scene.

But that was later linked to unconnected incident involving another couple coincidentally in the shopping centre.

Skripal was regarded as a traitor in Russia where he was jailed for 13 years in 2006.

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