By Tarek Amara and Christian Lowe
TUNIS (Reuters) - A surge of anger in the streets over police repression and poverty swept Tunisia's veteran strongman leader from power on Friday, sending a chill through unpopular authoritarian governments across the Arab world.
President Zine al-Abedine Ben Ali stepped aside after two decades in power and looked to have flown to France, the former colonial power. Paris police said they were expecting him.
Ben Ali's prime minister told Tunisians he would steer the state until early elections. There was calm on the streets of Tunis under heavy security, but some analysts questioned whether the change of face at the top would satisfy the protesters.
After days of unrest that spread from provincial towns to the capital, leaving dozens dead as security forces struggled to contain angry young demonstrators, the government declared a state of emergency and imposed a dusk-to-dawn curfew.
The violence and rapid turn of events sent shockwaves across the Arab world, where similar authoritarian rulers are deeply entrenched, but face mounting pressures from growing young populations, economic hardship and the appeal of militant Islam.
The United States led international calls for calm and for the people of Tunisia to be given a free choice of leaders. But Western powers have long turned a blind eye to rulers in the region who provide a bulwark against Islamist radicals.
French President Nicolas Sarkozy said: "Only dialogue can bring a democratic and lasting solution to the current crisis."
Tunis appeared quiet after the announcement on state television by Prime Minister Mohamed Ghannouchi that he would act as president until elections could be held. It was not clear whether his taking charge would satisfy the protesters, however.
And it remained uncertain how far those around Ben Ali, only the second president Tunisia has had since independence from France, were ready to relinquish power to opposition groups.
"Since the president is temporarily unable to exercise his duties, it has been decided that the prime minister will exercise temporarily the duties," Ghannouchi said.
CALL FOR UNITY
"I call on the sons and daughters of Tunisia, of all political and intellectual persuasions, to unite to allow our beloved country to overcome this difficult period and to return to stability."
The latest unrest was sparked when police prevented an unemployed graduate from selling fruit without a licence and he set fire to himself, dying shortly afterwards of his burns.
"Perhaps all the Arab governments are monitoring with eyes wide open what is happening in Tunisia," columnist Abdelrahman al-Rashed wrote in regional newspaper Asharq al-Awsat.
"Much of what prevents protest and civil disobedience is simply the psychological barrier," he said in an article after Ben Ali had made sweeping concessions but before he quit.
"But the psychological barrier is broken."
In power since 1987, Ben Ali had declared a state of emergency earlier on Friday and said protesters would be shot in an increasingly violent confrontation. He had also dismissed the government and called an early parliamentary election.
As the violence escalated, police 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, but only at the end of his current term in 2014.
Opposition leader Najib Chebbi, one of Ben Ali's most outspoken critics, described the events as a "regime change".
"This is a crucial moment. There is a change of regime under way. Now it's the succession," he told France's I-Tele TV.
"It must lead to profound reforms, to reform the law and let the people choose."
The White House said Tunisians should have the right to choose their own leader. It was monitoring developments in Tunisia and called on authorities there to respect human rights.
"We condemn the ongoing violence against civilians in Tunisia, and call on the Tunisian authorities to fulfil the important commitments ... including respect for basic human rights and a process of much-needed political reform," White House spokesman Mike Hammer said in a statement.
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.
BAN URGES RESTRAINT
U.N. Secretary Ggeneral Ban Ki-moon urged restraint.
"The political situation is developing fast and every effort must be made by all concerned parties to establish dialogue and resolve problems peacefully to prevent further loss, violence and escalations," he said. "And I will continue to discuss this matter with the concerned parties."
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 km (6 miles) 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. (Additional reporting by Stephanie Nebehay in Geneva, John Irish, Brian Love and Laure Bretton in Paris; writing by Maria Golovnina, editing by Alastair Macdonald)
