Until a few days ago, U.S. and British government inves-tigators had never heard of anyone being poisoned by the obscure and unstable isotope polonium-210. Now its extreme rarity is adding to the riddles in the death of exiled former Rus- sian spy Alexander Litvinenko, an outspoken critic of Russian President Vladimir Putin. Just before falling ill, the dissident received a document that seemed to warn of threats from an alleged secret fraternity of former KGB men calling themselves "Dignity and Honor," says Lord Tim Bell, a former Margaret Thatcher adviser close to Litvinenko's circle.
Who silenced Litvinenko? His family and supporters insist Russian agents did it. Investigators in London think such a lethal dose must have been industrially produced--a job that usually takes not only bismuth metal for raw material but a nuclear reactor to bombard it with neutrons. "It's not something you can go into a drugstore and get off a shelf," says a nuclear-agency official, asking to be nameless because of the sensitive topic. "To get this amount of highly concentrated radioactivity would take a very sophisticated operation, access to nuclear materials and support systems," Litvinenko's friend and fellow Russian exile Alex Goldfarb told news-week. Last week he released a statement he says was dictated by Litvinenko as he died, blaming Putin for the poisoning: "The howl of protest from around the world will reverberate, Mr. Putin, in your ears for the rest of your life."
Putin denied that he or his government had anything to do with Litvinenko's death. British officials say Moscow has made a serious effort recently to improve ties with London, and Litvinenko was not a big enough threat or nuisance for Putin to jeopardize so much hard work. Still, exotic poisons have been a favorite weapon of Moscow's spy services and their allies ever since Soviet times. The Brits are especially unlikely to forget the Bulgarian dissident who was murdered with a ricin-tipped umbrella on a London street in 1978.
The Soviet collapse did not end the sneak tactics. In 2002 a Saudi-born rebel leader in Chechnya known as Khattab reportedly died after being given a poison-soaked letter. A massive dose of dioxin disfigured and nearly killed the then Ukrainian presidential candidate Viktor Yushchenko in 2004. That same year, the Russian investigative journalist Anna Politkovskaya nearly died after drinking a cup of tea she later said had been poisoned. This October she was found shot dead in Moscow. Litvinenko publicly blamed Putin for her death--and fell ill less than two weeks later. Earlier this year, the Russian Parliament explicitly authorized the use of force against enemies living abroad. It's hard to think why Russian agents would use such a distinctive poison. But if they didn't, who did?