Tunisia has imposed a nationwide overnight curfew after protests and violence against rising unemployment spread across the country.

The curfew, to be imposed from 8pm until 5am, was announced after skirmishes between police and protesters in the early hours of Friday in the impoverished suburbs of Tunis. The capital is braced for mass protests this weekend.

The violence followed a week of unrest across the country, which police said had injured 59 officers and 40 protesters. The protests carry echoes of Tunisia’s Arab spring revolution in December 2010, which saw the downfall of the former president Zine al-Abidine Ben Ali.

“We have the freedom, but you cannot eat freedom,” said one unemployed graduate, Saber Gharbi, “There is a big similarity between 2011 and now. The same people are in the street for the same reason.”

“It’s been four years I’ve been struggling. We’re not asking for much, but we’re fighting for our youth. We’ve struggled so much for them,” Leila Omri, the mother of an unemployed graduate in Kasserine, told Associated Press.

In the clashes on Friday, molotov cocktails were thrown at police while gangs of youths looted shops, warehouses and a bank in the capital’s Ettahamen and Sidi Hassan districts. The prime minister, Habib Essid, cut short a visit to the World Economic Forum in Davos and was due to meet a delegation of protesters.

The country is already under a state of emergency, which was declared after a suicide bomber killed 12 members of the presidential guard in central Tunis in November.

Rioting against unemployment began last Sunday, when a young protester, Ridha Yahyoui, angry at being denied a government job, scaled a pylon in the southern town of Kasserine and was electrocuted.

Violence in Kasserine, one of the poorest cities in Tunisia, has since spread to eight more towns and cities. Riot police, troops and armoured cars have been deployed along the capital’s leafy Habib Bourguiba Avenue.

In Tunisia’s Arab spring revolution, the spark for dissent was also the death of a young protester, a market trader who set himself ablaze in the town of Sidi Bouzid. Within a month the dictator Ben Ali had fled and democracy was proclaimed.

But while Tunisia’s democracy has endured, even as the fellow Arab spring states Egypt, Libya and Syria have fallen into war or dictatorship, prosperity has not come with it.

Joblessness now stands at 15%, higher than the 12% at the time of the revolution. The International Labour Organisation reports that among young people the figure is double the national average, at 32%, rising to 40% in rural areas.

The World Bank says economic reform has been frustrated by the inability of successive governments to grapple with byzantine laws enacted to benefit the elite of the Ben Ali regime.

“Tunisia has become a more, not less, unequal society in the past decade,” the World Bank said in a recent report. “Its richer coast is at odds with its poorer interior. Its largest coastal cities – Tunis, Sfax and Sousse – account for a whopping 85% of its GDP and most of its industries and services.”

The economy was also hit hard by terrorist attacks last year at the capital’s Bardo museum and a beach resort in Sousse. There have been mass hotel closures and fears for the jobs of 400,000 Tunisians employed by the tourism industry. Away from the coastal cities, a climate of hopeless and despair has taken root among the young.

“Politically, Tunisia has done well, the political transition has succeeded, but the economic side has been a disaster,” said Michael Willis, an Oxford University professor. “You still have the old corrupt structures of the Ben Ali regime in place. I think this [protest] has been coming for a while.”

Compounding the economic misery has been falling demand from Europe, which accounts for nearly three-quarters of Tunisia’s exports.

Meanwhile, the country is dealing with the fallout from civil war in neighbouring Libya. And domestic politics are also fraught, with the ruling Nidaa Tounes (Call of Tunisia) party split in a leadership crisis over the enhanced role of President Beji Caid Essebsi’s son Hafedh, who party rebels complain is being groomed as his father’s successor.

Western powers have promised more support, with the United States quadrupling security aid and the European Union promising more assistance. The country’s profile was boosted last month when the Nobel peace prize was awarded to a quartet of civic organisations praised for preserving democracy during a political crisis two years ago.