It was in Sidi Bouzid where a vegetable seller set himself ablaze in a protest that sparked nationwide protests and eventually led to uprisings across the Arab world.

"We call for calm among the inhabitants of Sidi Bouzid, the cradle of the revolution which must be at the forefront of preserving the public good," said Rachid Ghannouchi, founder of the Ennahda, or Renaissance, party which took 90 of the assembly's 217 seats.

The assembly will be tasked with appointing a transitional government and writing the new constitution.

The local Ennahda bureau was among buildings burned in the unrest. Police lobbed tear gas to disperse a crowd of up to 3,000 people on Thursday night and the army fired warning shots, according to town resident Mourad Barhoumi. Residents burned tires, pillaged some stores and torched a National Guard post and a state training center, he said.

Authorities on Friday imposed a nighttime curfew, Interior Ministry spokesman Hichem Meddeb said.

The protests were linked to the party coming in fourth in the voting – the Areedha Chaabiya, or Popular Petition party. Its leader, Hachemi Hamdi, of Sidi Bouzid, announced on national television that he was withdrawing the 19 seats his party won after the electoral commission invalidated six of its seats.

Hamdi, owner of the Mustaqila satellite television channel based in London, had broadcast promises to give Tunisians free health care, new factories and thousands of jobs.

Electoral officials ultimately invalidated five lists tarnished by financing violations and one led by a former member of the ruling party – now banned.

Ghannouchi's long-banned Ennahda party has promised to create a broad-based coalition as it works to form a government to replace interim leaders who have run Tunisia since ousted President Zine El Abidine Ben Ali fled to Saudi Arabia on Jan. 14, chased away after a month of protests.

Potential partners are the Congress for the Republic party, founded in 2001 and which came in second place with 30 seats, and the third-placed Ettakatol party, which won 21 seats.

Congress for the Republic is headed by noted human rights activist Moncef Marzouki, a doctor who had lived in exile in Paris. Ettakatol, or the Democratic Forum for Labor and Freedoms, is led by Mustapha Ben Jaafar, also a doctor.

Ghannouchi, who spent more than two decades in exile in London, reiterated reassurances that his party would not impinge on women's rights in this Muslim Arab country.

"The program aims to strengthen the role of women, on the social as well as political level," he said.

Some Tunisians have feared a victory for the Islamist Ennahda might mean a rolling back of some of the country's more secular traditions.

U.S. State Department spokeswoman Victoria Nuland congratulated Tunisia on its successful elections and said the U.S. would judge Tunisia's parties by their respect for core democratic principles: freedom of speech, expression and media, and tolerance of differing views.

Britain's Middle East Minister Alistair Burt, meanwhile, expressed hope that the positive atmosphere in the run-up to elections would be replicated in the process of forming a coalition government and writing the new constitution.

"It is important that they fulfill the aspirations of the Tunisian people by respecting the principles of democracy, pluralism, rule of law and human rights," he said.