Who poisoned Yushchenko?

The Times is reporting "Doctors at the Austrian clinic that treated Ukraine’s opposition leader confirm there was a plot to kill him"

MEDICAL experts have confirmed that Viktor Yushchenko, Ukraine’s opposition leader, was poisoned in an attempt on his life during election campaigning, the doctor who supervised his treatment at an Austrian clinic said yesterday.
Doctors at Vienna’s exclusive Rudolfinerhaus clinic are within days of identifying the substance that left Mr Yushchenko’s face disfigured with cysts and lesions, Nikolai Korpan told The Times in a telephone interview.
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