Tunisian special forces fought a heavy gun battle with members of the ousted president's security force tonight, a military source said, and the prime minister promised a new government would be announced tomorrow.
Fighting erupted near the presidential palace in a Tunis suburb in the evening, the source said, following other gun battles in the capital two days after Zine al-Abidine Ben Ali was ousted after more than 23 years as president.
However, prime minister Mohamed Ghannouchi promised rapid action to fill the power vacuum. "Tomorrow we will announce the new government which will open a new page in the history of Tunisia," Mr Ghannouchi said in a brief statement.
The military source, who did not want to be identified, said people loyal to the arrested head of Mr Ben Ali's security force had opened fire as they passed near the front of the palace.
The clashes suggested a worsening of violence following drive-by shootings and jailbreaks yesterdayin which scores of inmates were killed.
State television reported earlier that two other gun battles had broken a relative calm enforced by the army in Tunis, one near the central bank building and another outside an opposition party's headquarters about one kilometre away.
Military and police sources said security forces had killed two gunmen stationed on a rooftop near the central bank, state TV's reporter said from the scene, a block from the interior ministry. A military official told the station that the two men had been killed by fire directed from a helicopter.
Earlier, the opposition PDP party said police and military had stopped a carload of armed men and shots were fired outside its headquarters. Police said two of the suspects caught after chasing them into apartment buildings had Swedish passports, and they also arrested a Tunisian.
Police detained four people carrying German passports over the same incident, state TV said, quoting a security source.
The official who was in charge of security for ex-president Zine al-Abidine Ben Ali, who fled the country on Friday after a wave of rioting, is to appear in court on charges of stoking violence and threatening national security. Al Jazeera television said a replacement had been appointed.
Today, tanks were stationed around Tunis and soldiers were guarding public buildings. Residents, some of whom had said they were starting to get back to normal life during daylight hours, rebuilt makeshift barricades from branches and trash cans to block their streets and protect property as the night curfew approached.
"We came out on the streets and dressed in white vests so we can identify one another. We told the police in the neighbourhood that we are here and we're dressed in white - it was during curfew hours ... some brought sticks and we collected rocks," one man said earlier in the day.
Analysts say there may be more protests if the opposition believes it is not sufficiently represented in a new government.
Sunday was not a working day but some people were shopping for food. For the first time in days, a few vans and pick-up trucks were making deliveries.
On the highway heading north into Tunis, a group of youths with sticks and knives were stopping private cars and robbing them just a few kilometres from an army checkpoint, a Reuters Television crew said.
Showing their contempt for Ben Ali's family, several hundred people filed through the empty, ransacked home of the former president's nephew, Kaif Ben Ali, taking photographs, picking up plants as souvenirs and stripping out plumbing fixtures.
The villa is in the chic Mediterranean resort of Hammamet, about 60 kilometres from the capital, where many of the moneyed elite close to the ousted president had their homes.
The speaker of parliament Fouad Mebazza, sworn in as interim president, has asked prime minister Mohamed Ghannouchi to form a government of national unity and constitutional authorities said a presidential election should be held within 60 days.
Mr Ghannouchi was holding more talks on Sunday to try to fill the vacuum left when Mr Ben Ali, president for more than 23 years, fled to Saudi Arabia following a month of protests over poverty, jobs and repression that claimed scores of lives.
While there have been relatively positive noises from the talks so far, the negotiations may run into trouble when they get down to the detail of which parties get which cabinet posts and how many of the old guard are included.
Ahmed Ibrahim, head of the opposition Ettajdid party, said he and other party leaders would meet Mr Ghannouchi. "The main thing for us right now is to stop all this disorder. We are in agreement on several principles concerning the new government. We will continue to discuss. My message is to say no to Gaddafi: we do not want to go backwards," he said, in reference to a speech by Libyan leader Muammar Gaddafi who said Tunisians were too hasty to get rid of Mr Ben Ali.
Opposition parties want assurances that presidential elections will be free, that they will have enough time to campaign, that the country will move towards greater democracy and that the power of the ruling RCD party will be loosened.
Two opposition parties have already said the two-month deadline for holding elections is too soon.
Opposition leader Najib Chebbi said after talks with Mr Ghannouchi yesterday that elections could be held under international supervision within six or seven months.
Beirut-based commentator Rami Khouri said it could take a while for Tunisia's opposition of secularists, leftists and Islamists to coalesce because there was no unified movement.
The ousting of Tunisia's president after widespread protests could embolden Arab opposition movements and citizens to challenge entrenched governments across the Middle East.
"It was always said that the Arab world was boiling but the continued state of stagnation made some doubt infiltrate minds. I think this doubt has now gone," Hany al-Masri, a Palestinian commentator based in Ramallah, said.
A military source said people still loyal to Mr Ben Ali were behind the drive-by shootings in Tunis today.Western and Arab powers have called for calm and unity.
Hundreds of European tourists, inlcuding a number of Irish nationals, stranded by the unrest were attempting to fly home on emergency flights.
Reuters