Three people have been killed and dozens were injured in extensive anti-government clashes outside the prime minister's office in the Albanian capital Friday, in the worst violence to erupt in the volatile Balkan country in more than a decade, AP news agency reports.

State health officials confirmed the three deaths following clashes between opposition supporters and riot police oustide the office of Prime Minister Sali Berisha. Some 22 civilians and 17 policemen and national guard officers were also hurt, the officials said.

More than 20,000 people hit the streets to demand that Berisha calls early elections after the country's deputy prime minister resigned over an alleged corruption scandal.

Clashes broke out when several hundred protesters broke away from the main group and started attacking a riot police cordon.

Chanting "Get out, Get Out," some of the protesters overturned and torched cars, smashed paving stones and hurled them at riot police and reached the steps of the government building.

Police responded with tear gas, plastic bullets and water canons. As the night fell, hundreds of riot policemen and national guard officers swept through the center of the capital, beating protesters with batons and detaining dozens of youths. Police did not say how many people were arrested.

President Bamir Topi urged rival political leaders to start an urgent dialogue to defuse the tension.

Opposition leader Edi Rama also called for calm, but said Berisha should also heed the message from the mass protest.

"My call is for the so-called prime minister not to go any further down the blind alley," Rama said.

The violence follows months of tension between the government and opposition Socialists that was rekindled this week by allegations of corruption.

Rama urged supporters to rally peacefully, and organizers of Friday's rally said they were trying to restrain the crowd.

The U.S. Embassy has also called for the protest to be peaceful and called on politicians, too, to tone down their inflammatory rhetoric.

The Socialists have accused Berisha's conservative Democratic Party of rigging the 2009 general election, which it won by a narrow margin. The next general election is scheduled for 2013.

Albania, a new member of NATO, is eager to show an improvement in its election standards and democratic institutions to gain eventual European Union membership.