Over 300 protesters have been arrested overnight and the army has been deployed in several Tunisian cities in response to violent demonstrations over prices, taxes and unemployment.
In Thala, near the Algerian border, troops were sent in after protesters burned down the national security building forcing police to retreat from the town, witnesses told Reuters.
Violent anti-government protests have raged in other towns in the North African country since Monday, among them the tourist resort of Sousse, against price and tax rises imposed by government to cut a ballooning deficit and satisfy international lenders.
While Tunisia is widely seen as the only democratic success story among "Arab Spring" nations, it has also had nine governments since the overthrow of authoritarian leader Zine El-Abidine Ben Ali, none of which have been able to deal with growing economic problems.
"Three hundred and thirty people involved in acts of sabotage and robbery were arrested last night," interior Ministry spokesman Khelifa Chibani said, bringing the number of detainees since the protests began to around 600.
The army was also deployed in several other cities, including Sousse, Kebeli and Bizert to protect government buildings that have become a target for protesters.
Prime Minister Youssef Chahed on Wednesday accused the opposition of fueling dissent by calling for more protests.