New violence erupted in Ukraine's capital during the night as a large crowd attacked a government exposition and conference hall where police were stationed inside.
Early Sunday, demonstrators were throwing firebombs into the Ukrainian House building and setting off fireworks, and police responded with tear gas. Although the crowd created a corridor at the building's entrance apparently for police to leave, none were seen coming out.
The outburst underlined a growing inclination for radical actions in the protest movement that has gripped Kiev for two months. The building under attack is about 250 yards down the street from Independence Square, where mostly peaceful demonstrations have been held around the clock since early December and where protesters have set up an extensive tent camp.
Clashes with police broke out a week ago in the wake of new, harsh anti-protest laws.
More-moderate opposition figures, including heavyweight boxing champion Vitali Klitschko, have tried appealing to stop the clashes, but have been booed, and one time Klitschko was sprayed with a fire-extinguisher.
Another top opposition figure, Arseniy Yatsenyuk, said Saturday that the protests will continue despite the offer by embattled President Viktor Yanukovych to make him prime minister.