TUNIS, Tunisia – Looting, deadly prison riots and street chaos engulfed Tunisia on Saturday, a day after mass protests forced its strongman to flee. A new interim president was sworn in, promising to create a unity government that could include the long-ignored opposition.

It was the second change of power in this North African nation in less than 24 hours.

Amid the political instability, looters emptied shops and torched the main train station in Tunis, soldiers traded fire with assailants in front of the Interior Ministry, and thousands of European tourists sought plane flights home.

The death toll mounted. At least 42 people were killed Saturday in a prison fire in one resort town and the director of another prison in another tourist haven let 1,000 inmates flee after soldiers shot five dead amid a rebellion. Those deaths came on top of scores of others after a month of protests in which police often fired upon demonstrators.

After 23 years of autocratic rule, President Zine El Abidine Ben Ali abruptly fled the country Friday for Saudi Arabia after mass street protests over corruption, a lack of jobs and clampdowns on civil liberties.

The leadership changes then came at a dizzying speed.

Ben Ali’s longtime ally, Prime Minister Mohammed Ghannouchi, stepped in briefly with a vague assumption of power that left open the possibility that Ben Ali could return.

But on Saturday, the head of the Constitutional Council declared the president’s departure permanent and gave Fouad Mebazaa, leader of the lower house of parliament, 60 days to organize new elections. Hours later, Mebazaa was sworn in.

In his first televised address, the interim president asked the premier to form a “national unity government in the country’s best interests” in which all political parties will be consulted “without exception nor exclusion.”

The move was one of reconciliation, but it was not clear how far the 77-year-old Mebazaa, who has been part of Tunisia’s ruling class for decades, would go to work with the opposition.

It was also unclear who would emerge as the country’s top political leaders, since Ben Ali utterly dominated politics, placing allies in power and sending opponents into jail or exile.

On the streets, the unrest was frightening. A fire Saturday at a prison in the Mediterranean coastal resort of Monastir killed 42 people, coroner Tarek Mghirbi said.

In Mahdia, farther down the coast, inmates set fire to their mattresses in protest. Soldiers opened fire, killing five inmates, a top local official said. The director of the prison then let about 1,000 other inmates flee the prison to avoid further bloodshed, the official said.

In front of the Interior Ministry in Tunis, security forces and unidentified assailants had a shootout Saturday that left two bodies on the ground.