|At least three people were killed during the protests in the capital Tirana [AFP]
Four people have been killed and dozens injured in extensive anti-government clashes outside the prime minister's office in Tirana, the Albanian capital.
State health officials confirmed the four had died from gunshot wounds during the clashes between opposition supporters and riot police.
About 30 civilians and 25 policemen and national guard officers were also hurt, the officials said.
The violence follows months of tension between the government of Sali Berisha, the prime minister, and opposition Socialists.
Speaking to Al Jazeera, Karolina Risto, chief editor at Albania's Vision Plus TV, said: "Albania is finally calm now after more than six hours of violent clashes.
"Four people are reported dead, all of them young men among the demonstrations in Albania's capital.
"The whole purpose of this gathering is because the opposition is accusing the government of stealing their votes in the last election."
Berisha called the protests an opposition attempt to foment a Tunisia-style uprising.
"The bastard children of Albania's own Ben Alis conceived Tunisian scenarios ... for you citizens of Albania," he said, comparing his Socialist political opponents with the ousted Tunisian president Zine El Abidine Ben Ali
The violence was the worst since the storming of the government building after the death of a politician in 1998.
"Albania is not in a state of emergency and will not pass into a state of emergency. But scenarios of violence will not be tolerated," Berisha said.
More than 20,000 people took to the streets on Friday to demand that Berisha call early elections after Ilir Meta, the country's deputy prime minister, resigned over an alleged corruption scandal earlier this week.
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 centre of the capital, beating protesters with batons and detaining dozens of youths.
Police did not say how many people were arrested.
In a statement, the US, OSCE and European Union expressed "deep regret" at the violence
"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 text read.
The statement also renewed a call for "constructive dialogue and compromise to resolve the existing political differences".
Bamir Topi, the president, urged rival political leaders to start an urgent dialogue to defuse the tension.
Edi Rama, an opposition leader, also called for calm, but said Berisha should also heed the message from the mass protest. He also 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," he said.
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, one of Europe's poorest countries, is a NATO member, and is also seeking EU membership, but corruption is believed to be pervasive and there is widespread unemployment.