Violent protests erupted on Tunisia's streets again today as the country struggled to deal with the aftermath of overthrowing its president.

Police fired tear gas and rioters smashed police cars as tensions resumed in the capital Tunis.

Scores of protesters from Tunisian provinces gathered in front of the prime minister's office, shouting anti-government slogans and breaking windows of cars nearby.

The crowd included people who had defied a nationwide curfew and staged a sleep-in overnight.

Schools were due to reopen today after protracted closure amid the unrest, but teachers went on strike.

The protesters are angry that remnants from former president Zine El Abidine Ben Ali's regime hold leading posts in the interim government in place since last week.

Ben Ali fled the country on January 14 after 23 years in power, pushed out by weeks of deadly protests driven by anger over joblessness, corruption and repression.

Noisy street demonstrations have continued since his departure, but most have been peaceful.

State TV also reported today that a former Ben Ali political adviser who had been sought by police, Abdelwaheb Abdallah, had been found and placed under house arrest.

Police have cracked down on key allies of the former president, placing two high-ranking officials under house arrest and detaining the head of a popular private TV station for allegedly trying to slow down the country's steps toward democracy.

Tunisia's "Jasmine Revolution" sparked scattered protests and civil disobedience across the Middle East and North Africa. Many observers were looking to see if Tunisians can complete their fervent push for democracy.

Prime Minister Mohamed Ghannouchi, who took the post in 1999 under Ben Ali and has kept it through the upheaval, has vowed to quit politics after new elections. But he has insisted that he needs to stay on to shepherd Tunisia through a transition to democracy. Many other cabinet members are also from the Ben Ali-era .