Armoured vehicles were seen patrolling the streets of Tunis and soldiers took up positions at major intersections early on Wednesday. Troops were also deployed in the west of the capital where recent clashes have taken place.
On Tuesday, protesters threw stones at riot police in the Tunis suburb of Ettadamen. A bus and several cars were also torched outside government buildings, which were attacked by rioters.
It is the first time troops were deployed in the capital since unrest broke out in the south of the country mid-December.
Protests in Tunisia over the cost of living and high levels of unemployment were sparked by the suicide of a graduate who was prevented by police from selling fruit and vegetables to make a living.
Tunisian Interior minister Rafik Belhaj Kacem has been fired in the wake of the riots, Tunisia’s PM Mohamed Ghannouchi said on Wednesday.
At a press conference in Tunis, Ghannouchi also said all those arrested during the protests would be released.