Tunisia is considered a rare success story of the Arab Spring uprisings that began in the North African country in 2011 and spread across the region, toppling autocrats.
But the authorities have failed to resolve the issues of poverty and unemployment.
Police detained 328 people on Wednesday for theft, looting, arson and blocking roads, the interior ministry said, after arresting more than 280 people over the previous two days.
The latest unrest overnight saw a provincial police station torched, Molotov cocktails hurled at police and tear gas fired, but ministry spokesman Khalifa Chibani said the "violence" was less intense than in previous days.
Twenty-one members of the security forces were injured, according to Chibani, who said no civilians were hurt.
Tunisia is often seen as having had a relatively smooth transition since the 2011 uprising that toppled long-time dictator Zine El Abidine Ben Ali.
But Tunisians have expressed frustration since the start of the year over austerity measures expected to further increase prices in a struggling economy.
The North African country introduced hikes in value-added tax and social contributions as part of a tough new budget.
"Young people are disappointed with the revolution, especially because of the high cost of living," she said.
Lamloum pointed to "deepening social inequalities" highlighted by official figures showing rising poverty, unemployment and illiteracy, particularly among young people.
A Tunisian employers' federation announced it was bringing forward the winter sales to January 20 in consultation with the commerce ministry to boost people's purchasing power.
Conflict analysts International Crisis Group (ICG) warned the country's political class Thursday against succumbing to "authoritarian temptation".
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)