>> The collapse of a former Russian double agent in a quiet English town, and the absence of many facts surround why Sergei Skripal and his daughter are critically ill, has raised questions about whether the pair were singled out. Critics or enemies of Moscow have been victims of poisoning, or at least suspected it, in the past.
During the Cold War, Georgi Markov, a Bulgarian dissident, was killed in London with a poison-tipped umbrella. This reenactment of the moment portrays Markov waiting for a bus when he felt a sharp sting in his thigh. A stranger fumbled behind him with an umbrella before walking away. Markov later died of what's believed to be ricin poisoning.
Dissonance accused the Soviet KGB of being behind the killing. Ex-KGB agent, Alexander Litvinenko, died after drinking green tea laced with radioactive polonium-210 at London's Millennium Hotel. A British inquiry concluded in 2016, ten years after his death, that Russian President, Vladimir Putin, probably approved the killing. The Kremlin has denied any involvement.
An outspoken critic of Putin, Litvinenko, fled Russia for Brittain six years to the day before he was poisoned. In 2004, Viktor Yushchenko was campaigning on a pro western ticket for Ukraine's presidency. In the lead up to the election, he was poisoned with 1,000 times more dioxin than is normally present in the human body, disfiguring his face and limbs.
Yushchenko subsequently won the presidency in a rerun poll. He says he was poisoned while having dinner outside Kiev with officials from the Ukrainian security services. Russia denied any involvement. Other suspected cases involved a 44 year old Russian, found dead near his luxury London home in 2012, with traces of a rare and deadly poison from the Gelsemium plant in his stomach.
While Russian opposition activist, Vladimir Kara-Murza, believed there were attempts to poison him from 2015. A German laboratory later found elevated levels of Mercury, Copper, Manganese, and Zinc in his system. Again, Moscow claimed it wasn't involved in either case.