Tunisian special forces fought a heavy gun battle with members of the ousted president's security force on Sunday, reports say.
A military source said fighting erupted near the presidential palace in Tunis, following other gun battles in the capital two days after Zine al-Abidine Ben Ali went fled the North African nation.
Earlier, security forces fought a gun battle with stationed on a rooftop near the central bank headquarters, state television reported. Military and police sources said security forces had killed the gunmen.
Shots were fired outside an opposition party headquarters after police and military stopped a carload of armed men.
Weeks of violent protests over poverty, jobs and repression and a popular uprising forced President Zine al-Abidine Ben Ali to flee to Saudi Arabia on Friday after 23 years in power.
The official who was in charge of security for the ousted president is to appear in court on charges of stoking violence and threatening national security.
Interim president Fouad Mebazza 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.