Ben Ali's government had called a curfew in the capital in a bid to put a lid on the deadly unrest [AFP]

At least six people have been killed in renewed clashes in Tunisia, in spite of a dusk-to-dawn curfew in the capital, Tunis, and surrounding suburbs.

Clashes erupted early on Thursday in the district of al-Kerm, north of Tunis, witnesses told Al Jazeera. Those killed include three people in the town of Menzel Bourguiba, one person in Bizerte, and one person in Tataouine.

Eye witnesses also said that a sixth person was killed in the capital after a curfew was imposed. There have also been violent clashes with police reported in Douz.

Sources told Al Jazeera that protesters chanted anti regime slogans in several Tunisian cities, including Bizerte, Sidi Bouzid and Kairouan.

The deaths come against a backdrop of clashes between police and stone-throwing youths who are angry about high unemployment and rising food prices.

Sporadic gunfire rung out overnight outside Tunish, indicating youths had defied the curfew order from Zine El Abidine Ben Ali's government.

Officials had enacted the curfew in a bid to put a lid on unrest that has left at least 23 people dead across the country, according to a government toll.

But labour and rights groups have said the death toll is much higher.

Navi Pillay, the UN high commissioner for human rights, called on the Tunisian government on Thursday to investigate reports of police killings of civilians.

"We are trying to verify the number killed. Human rights organisations report almost 40 killed. So clearly that is a result of some excessive measures used, such as snipers, the indiscriminate killing of peaceful protesters," she told the Reuters news agency.

Emergency parliament session

Ben Ali was expected to appear before parliament on Thursday for an emergency session to address the unrest.

His appearance would come a day after he sacked Rafik Belhaj Kacem, his interior minister, who was widely criticised for the government's heavy-handed response to the protests.

Read more about Tunisia's unrest on the spotlight page

However, the firing did little to calm the situation as hundreds of protesters hurled stones at police at a key intersection in Tunis on Wednesday.

Officers responded with volleys of tear gas, driving the protesters to disperse into adjoining streets. Stores in the area were shuttered.

Tunis had been spared the protests that began in mid-December, and turned violent in the west of the country at the weekend when security forces opened fire on demonstrators, until Tuesday when rioters attacked a local government office in the Cite Ettadhamen quarter.

Mohamed Ghannouchi, the prime minister, said on Wednesday that all those arrested in the wave of demonstrations had been released, but gave no figure for how many had been originally detained.

Ben Ali, the president, had only a few days earlier accused the rioters of committing acts of "terrorism".

Ghannouchi also said that allegations by opposition and non-government groups into corruption would be investigated by a special commission.

'Significant' measures

Ayesha Sabavala, a Tunisia analyst is with the Economist Intelligence Unit, told Al Jazeera that the government's measures were significant.

"The government is trying to tell people that 'we know we have made mistakes and we know there is widespread discontent, we are trying to address theses issues'," she told Al Jazeera from London.

"But the president himself, in his speech on January 10, promised the creation of 300,000 jobs in the next two years, which in my opinion is highly ambitious given Tunisia growth rate."

Radwan Masmoudi, an expert on Tunisia, told Al Jazeera that Ben Ali's change of direction is a beginning, but people's demands are for greater reform and genuine democracy.

"I think it has finally dawned on the president that these demands are not going to go away," Masmoudi said.

"He realises he has to make some serious changes and not just of people but in policies.

"People see corruption as the main problem in Tunisia so there is a tie between economic development and political institutions to guard against corruption."

The rare unrest in tightly controlled Tunisia was unleashed by the suicide of a 26-year-old man who set himself on fire on December 17 after police prevented him from selling fruit and vegetables to make a living.

Source: Al Jazeera and agencies