Tunisian President Zine al-Abedine Ben Ali stepped aside on Friday after failing to quell the worst anti-government unrest in his two decades in power. Al Jazeera TV said Ben Ali had left the country.
In a television address in Tunis, Prime Minister Mohamed Ghannouchi said he had taken over as interim president, and vowed to respect the constitution and restore stability.
In power since 1987, Bel Ali had earlier declared a state of emergency and said protesters would be shot in an increasingly violent confrontation that has sent shockwaves across the Arab world, where authoritarian rule is the norm.
Ben Ali had earlier dismissed the government and called an early parliamentary election.
Tunisia's problems are shared by other countries in the region, the latest unrest was sparked when police prevented an unemployed graduate from selling fruit without a license and he set fire to himself, dying shortly afterwards of his burns.
Police had fired tear gas to disperse crowds in central Tunis demanding his immediate resignation. They were not satisfied with his promise on Thursday to step down in 2014.
"This state of emergency means that any gathering of more than three people is forbidden, that arms will be used by security forces in cases where a suspect does not stop when asked to do so by the police," state television said.
Western countries urged their people to avoid travel to the popular tourist destination due to the instability.
Medical sources and a witness said 12 people died in overnight clashes in Tunis and the northeastern town of Ras Jebel.
Before the latest casualties, the official death toll in almost a month of violence was 23. The Paris-based International Federation for Human Rights said it had a list of at least 66 people killed.
After police fired tear gas and wielded their truncheons, crowds of youths retreated a little way from the building and started throwing stones at the police, who responded with more tear gas grenades. Reporters also heard gunfire nearby.
A Reuters photographer saw people looting two big supermarkets in the Tunis suburb of Enkhilet, about 10 kilometers from the capital. He said they had set fire to the local police station.
On almost every block in suburban Tunis, people were standing on the street with baseball bats to protect their cars and homes from damage by looters, a Reuters reporter said.
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