Tunisian authorities on Tuesday reported four more people killed in the worst civil unrest for decades, bringing the "official total" since last week to 18, but human rights groups put the death count higher.
The interior ministry said four civilians were killed in clashes on Monday in the town of Gassrine, a focus of recent protests.
The ministry in a statement defended the firings, as saying "the police were obliged to defend themselves. They fired warning shots in the air but the throwing of Molotov cocktails intensified and this caused four deaths among the attackers and eight cases of injuries and burns among the police."
Witnesses reported separately that anti-riot police fired tear gas as new protests broke out overnight in two western towns, despite a pledge by the president to create 300,000 jobs before the end of 2012.
(People carry a protestor killed in clashes with police on a stretcher near Sidi Bouzid in Tunisia January 10, 2011.)
The Tunisian government on Monday ordered the indefinite closure of all schools and universities in an attempt to stamp out clashes with police which it said killed 14 civilians at the weekend.
Amnesty International gave a figure of 23, while Souhayr Belhassan, who chairs the Paris-based International Federation for Human Rights (FIDH), told France Inter Radio it had a list of 35 people confirmed dead in the unrest. The figures were issued before the news of the deaths in Gassrine.
Protesters say they are demanding jobs, but President Zine al-Abidine Ben Ali, facing the worst unrest of his 23-year rule, said on Monday the rioting was a "terrorist act", orchestrated by foreign parties who were trying to damage Tunisia.
A few hopeful Tunisians trickled into a job centre in the capital on Tuesday, encouraged by the president's promise to cut graduate unemployment.
But the pledge failed to appease some poorer areas. Witnesses, who asked not to be named, said police fired tear gas to disperse protesters in the towns of El-Kef and Gafsa after Ben Ali's televised speech.
There were no immediate reports of casualties. Officials could not immediately comment on the accounts by witnesses.
Prior to the weekend clashes, at least four other people were killed, including two who were shot dead by the police and two others who took their own lives to protest against the lack of job opportunities in the Arab country of 10 million.
Ben Ali is bracing for greater scrutiny and pressure from the international community after the clashes. United Nations Secretary-General Ban Ki-moon expressed concern about the escalation of violence and called for restraint. The European Union, Tunisia's biggest trade partner, said it deplored the loss of life.
(A view of the site where protestors clashed with police near Sidi Bouzid in Tunisia January 10, 2011.)
Washington has already expressed concern about the Tunisian government's handling of the protests. The Tunisian Foreign Ministry said on Monday it had summoned the U.S. ambassador to Tunis to express its "astonishment" at Washington's stance.
The government sent the military onto the streets in the worst-hit areas late on Sunday in an effort to restore order.
In Tunis, which saw a rare protest by students on Monday, life seemed to be following a normal course, with shops open despite the decision to close schools.
The police presence appeared to have been beefed up in the capital, where Tunisian journalists plan to hold a protest later on Tuesday.
Assabah newspaper on Tuesday reported that Ben Ali had asked the chairman of the lawyers' association, Abderrazek Kilani, to "help ease the tension". Thousands of Tunisian lawyers went on strike last week to protest against alleged police beatings.
(A protestor killed in clashes with police lies on the ground near Sidi Bouzid in Tunisia January 10, 2011.)
In front of the Lafayette job centre in the capital, a handful of young Tunisians stood in line to see if they could take advantage of Ben Ali's job creation pledge.
"The president's speech gave us new hope ... I have a master's degree in economy and I have been jobless for four years. I hope I will get lucky and land a job soon," said Hamdi, from the provincial town of Sidi Bouzid.
It was in Sidi Bouzid that the initial protest broke out, when graduate Mohamed Bouazizi, 26, set himself on fire in front of a government building after police seized his unlicensed fruit and vegetable stall. Bouazizi died earlier this month of his burns.
Imen, waiting for her turn at the same job centre, struck a note of caution about Ben Ali's promises: "I hope the promises will become a reality".
Princesse El-Materi Holding, a company owned by Ben Ali's billionaire son-in-law Sakher Materi, also promised to employ 200 jobless graduates, Assabah added.