Thousands of opposition activists on Wednesday protested the arrest of former Prime Minister Yulia Tymoshenko, clouding official celebrations marking the 20th anniversary of Ukraine's independence declaration.
Over 5,000 demonstrators, many of them clad in traditional Ukrainian white embroidered shirts, attempted to march on the president's office in Kiev, but were held back by police in riot gear who flooded the city's center. Smaller groups of protesters were later allowed onto the capital's main avenue.
Tymoshenko's abuse-of-office trial and arrest this month on charges of contempt of court have galvanized Ukraine's notoriously fragmented opposition.
Wednesday's rally attracted a broad spectrum of government critics opposed to President Viktor Yanukovych's government and a trial they see as selective prosecution meant to bar Tymoshenko from upcoming elections.
Tymoshenko issued an appeal from jail, urging unity among the opposition. She vowed that current authorities will be prosecuted for what she called the crimes they are committing today.
Five years from now, "real, and not political, prisoners will be in jail; today we know their names," she said in a letter posted on her website.
"Happy holiday, my dear ones! This is our holiday! We will prevail, we will win! I promise!" she wrote.
She was arrested Aug. 5 on charges of contempt of court as part of a trial in which she stands accused of violating official procedures when signing a natural gas import contract with Russian in 2009.
Tymoshenko denies all the charges, and the United States and European Union have condemned the arrest and trial as politically motivated.
Yanukovych says the criminal cases against Tymoshenko and a number of her senior allies are part of a government effort to fight corruption.
Tymoshenko's arrest has threatened the prospects of Ukraine's integration with Europe, but Yanukovych maintained Wednesday that Ukraine was on a pro-Western course.
"Our history is inseparably linked with modern Europe," Yanukovych said in a statement on his website. "For centuries the best sons and daughters of Ukraine have dreamt of an independent country which is based on freedom, humanity and democracy. And their dreams have come true."
Ukrainian lawmakers declared the Soviet republic independent on Aug. 24, 1991, days after a failed hard-line Communist coup against Soviet President Mikhail Gorbachev.
Ukraine's voters overwhelmingly approved the decision in referendum that December, and it became independent later that month when Gorbachev resigned and the Soviet Union ceased to exist.