Tunisian protesters burned down a regional national security headquarters near the Algerian border, prompting authorities to send in troops after police retreated, witnesses said, as unrest over prices and taxes continued nationwide.
Over 300 protesters were arrested overnight and the army was deployed in several cities to help quell violent protests in Tunisia seven years after the overthrow of autocrat Zine El-Abidine Ben Ali in the first of the Arab Spring revolts.
In Thala, near the Algerian border, soldiers deployed after crowds torched the region's national security building, forcing police to retreat from the town, witnesses told Reuters.
Tunisia's unity government - which includes Islamists, secular parties and independents - has portrayed the unrest as driven by criminal elements, and Prime Minister Youssef Chahed has accused the opposition of fuelling dissent.
Rejecting that accusation, Tunisia's main opposition bloc, the Popular Front, called for a major protest in Tunis on Sunday to coincide with the seventh anniversary of Ben Ali's fall.
Tunisia's Football Association said it was postponing all weekend matches because of the disturbances.
Anti-government protests have flared in a number of Tunisian cities and towns - including the tourist resort of Sousse, since Monday against price and tax rises imposed to cut a ballooning deficit and satisfy international lenders.
Tunisia had nine governments since Ben Ali's overthrow, none of which have been able to deal with growing economic problems.
The army has been deployed in several cities, including Sousse, Kebeli and Bizerte, to protect government buildings that have become a target for protesters.
"Three hundred and thirty people involved in acts of sabotage and robbery were arrested last night," Interior Ministry spokesman Khelifa Chibani said. That brought the total number of detainees since the protests began to around 600.
"What is happening is crime, not protests. They steal, intimidate people and threaten private and public property," he added.
Many of the protests have been peaceful, however, with demonstrators expressing their anger and frustration over deepening economic hardship since the 2011 uprising.
"It is true that some protesters burned and stole during last night's protests, but the rulers steal and destroy Tunisia in the morning and at night with their frustrating decisions," said a teacher who was shopping in the capital and only gave his first name, Mohamed.
"We expected things to improve after Ben Ali was ousted, but it seems that after seven years of the revolution, we'll give our salaries each month to Prime Minister Chahed for him to spend them," he said.
Unemployment nationally exceeds 15 percent, and is much higher in some marginalised regions of the interior. Annual inflation rose to 6.4 percent in December, the highest rate since July 2014.
*This story was edited by Ahram Online.