Tensions that have been building for months between the government and opposition Socialists came to a head after a top minister was forced to resign this week amid an alleged corruption scandal.
More than 20,000 people hit the streets Friday to demand that Prime Minister Sali Berisha call early elections after the country's deputy prime minister, Ilir Meta, resigned. Opposition supporters battled riot police outside Berisha's office in Tirana, and health officials said three people were shot dead and 30 civilians and 24 policemen and National Guard were injured.
The United States and the European Union expressed "deep regret" at the violence.
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. That regime was toppled in a student-led revolt in 1990. The country is now a NATO member and seeks to join the 27-nation EU but corruption is believed to be pervasive and unemployment is high.
The corruption scandal broke after a private TV station aired a video allegedly showing Meta asking a colleague to influence the awarding of a contract to build a power station.
The Socialists have also accused Berisha's conservative Democratic Party of rigging the 2009 election, which it won by a narrow margin. The next election is scheduled for 2013.
Clashes broke out Friday when several hundred protesters broke away from the main group and started attacking a riot police cordon. Chanting "Get out, Get out!" some protesters overturned and torched cars, smashed paving stones and hurled them at riot police and reached the steps of the government building.
Police used tear gas and water cannons to beat them back. 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. There was no immediate word on arrests.
President Bamir Topi urged political leaders to defuse the tensions. Opposition leader Edi Rama also called for calm but said Berisha should heed the message from the protest.
"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 of 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 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 called for "constructive dialogue and compromise" to resolve differences between political groups.