In 2004, Viktor Yanukovych, then Prime Minister, was declared the winner of the presidential elections, which had been largely rigged, as the Supreme Court of Ukraine later ruled. The results caused a public outcry in support of the opposition candidate, Viktor Yushchenko, who challenged the outcome. During the tumultuous months of the revolution, candidate Yushchenko suddenly became gravely ill, and was soon found by multiple independent physician groups to have been poisoned by TCDD dioxin. Yushchenko strongly suspected Russian involvement in his poisoning. All of this eventually resulted in the peaceful Orange Revolution, bringing Viktor Yushchenko and Yulia Tymoshenko to power, while casting Viktor Yanukovych in opposition.