Clashes erupted Thursday between Tunisian police and jobless protesters, in the latest outbreak of social unrest in the neglected but resources-rich central Gafsa region, an AFP journalist reported.
The protesters placed burning tyres in the streets of Metlaoui, around 350 kilometres (220 miles) south of Tunis, and hurled rocks at the police who fired tear gas in response.
On Wednesday night, demonstrators set fire to the local office of Tunisia's main Islamist party Ennahda, and also partially damaged a court building, while on Tuesday night they torched a police post.
The riots were triggered by the announcement earlier this week of the results of a recruitment process by a public company operating in the environmental sector, which the protesters believe unfairly excluded them.
Social discontent in Tunisia often leads to violence, especially in the impoverished centre of the country, where a street vendor set himself on fire more than three years ago in a desperate act of protest that launched the first Arab Spring uprising.
Gafsa is economically important because of its phosphate mines, but remains among the poorest areas in Tunisia despite its natural wealth.
It saw anti-government protests in 2008 that were savagely repressed by the regime of former autocrat Zine El Abidine Ben Ali.
Unemployment was a driving factor behind the revolution that toppled Ben Ali and continues to affect some 15 percent of the economically active population, with the figure rising to more than 30 percent among school leavers.
Political instability, Islamist violence and social unrest have hampered Tunisia's economic recovery since the revolution.
Growth last year slowed to 2.6 percent last year, compared with 3.6 percent in 2012, according to figures announced by the central bank on Thursday.
It said the decline was explained "by the negative political and security factors that prevailed especially in the second half of the year, which in addition to the economic slowdown, put pressure on the country's financial stability."
Tunisia been hit since the 2011 uprising by sporadic violence linked to radical Islamists, who were blamed for the assassinations last year of two secular politicians.
The killings plunged the country into political turmoil and eventually forced the Ennahda-led government to resign last month.