TIRANA, Albania - 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.

State health officials confirmed three people had died from gunshot wounds during the clashes between opposition supporters and riot police outside the office of Prime Minister Sali Berisha. Some 30 civilians and 25 policemen and national guard officers were also hurt, the officials said.

The United States and European Union expressed "deep regret" at the violence which follows months of tension between the government and opposition Socialists that was recently rekindled this week after the country's deputy prime minister was forced to resign after an alleged corruption scandal.

Albania is one of Europe's poorest countries. For nearly 50 years, this mountainous country of 3.2 million people, was ruled by xenophobic Communists who banned contact with the outside world, before that regime was toppled in a student-led revolt in 1990. The country is now a NATO member, and is also seeking an EU membership, but the corruption is believed to be pervasive, as is unemployment.

More than 20,000 people hit the streets Friday to demand that Berisha calls early elections after the country's deputy prime minister, Ilir Meta, resigned over an alleged corruption scandal. The scandal broke after a private TV station aired a video allegedly showing Meta asking a colleague to influence the awarding of a contract for building a power station.

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.

Rama appeared to suggest that protests will continue.

"I assure all of you, we shall continue our struggle in a determined way, because the way out is clear: Either a free Albania for all, or keep the people subdued under the boot or barbaric power," Rama said.

The United States Embassy, the European Union Delegation and the Organization for Security and Cooperation in Europe issued a joint statement to say that they "deeply regret that today's demonstration in Tirana was not peaceful and resulted in some casualties.

"Violence and excessive use of force cannot be justified and should be avoided. We urgently appeal for calm and restraint on all sides and to abstain from provocations," the statement said.

They renewed the call for "constructive dialogue and compromise to resolve the existing political differences."

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.