KIEV, Ukraine -- In one of Ukraine's largest demonstrations in years, tens of thousands of held protests across the country Monday demanding that President Leonid Kuchma resign or call early elections.

In the capital Kiev, about 20,000 protesters from several opposition groups blocked the city's downtown area for hours, shouting "Away with Kuchma!"

Many marched to the presidential administration building, where they set up tents in heavy rain as night fell. They vowed to stay until Kuchma steps down.

It was one of the country's biggest demonstrations since Ukraine independence from the Soviet Union 11 years ago. Political tensions in Ukraine have been rising steadily since parliamentary elections in March, in which opposition parties won the bulk of the popular vote.

The demonstrators represented the full spectrum of Ukrainian politics, from communists to progressive reformers. All claimed Kuchma's government is so corrupt that democratic rule and economic development have been smothered.

"I'm here because of the unemployment, lack of money and ... the bleak future for my children and grandchildren," said Tetiana, an unemployed woman from the depressed eastern Luhansk region, who declined to give her last name.

Kuchma did not respond to the protests. He was in Austria on Monday, pressing political and business leaders to support Ukraine's distant hopes of joining the European Union.

The demonstration was timed to coincide with the second anniversary of the disappearance of investigative journalist Heorhiy Gongadze. The October 2000 discovery of a beheaded body, believed to be Gongadze's, sparked months of protests against Kuchma. Opposition groups accused him of being involved in the journalist's death, which he denies.

Kuchma was first elected in 1994 and re-elected five years later. His current term ends in 2004, and the constitution prohibits him from running again.