Who is former Russian spy Sergei Skripal?

  • By Nandini Krishnamoorthy

A retired Russian intelligence (GRU) colonel is in critical condition years after he was convicted by Moscow's military court of "high treason" for allegedly spying for the British. On Sunday (Mar. 4), he and a woman were found unconscious on a Salisbury, England, shopping center bench after exposure to an "unknown substance. The bizarre incident is drawing comparisons to the poisoning death of former Russian secret service officer and defector, Alexander Litvinenko. Russia has repeatedly denied any responsibility in Litvinenko's poisoning death but relations between Britain and Russia have been strained since the 2006 incident. 

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