In a remote town in Tunisia's interior, protesters angry over joblessness and harsh police tactics call for the downfall of new Islamist rulers, echoing the revolt that ignited the Arab Spring two years ago.

Siliana, 140 kilometres (90 miles) from the coastal capital, has been convulsed as thousands of largely unemployed youth battle riot police firing tear gas and birdshot.

"I lost my eye because of the police; this is what Ennahda has done," says Anis Omrani, 24, referring to the Islamist party that won the North African country's first free elections last year after the overthrow of dictator Zine Al-Abidine Ben Ali.

"We don't have jobs and we're marginalised, but they attack us savagely ... The police of Ennahda just add another problem," Omrani says, with a patch over one eye.

Of at least 252 wounded, medical sources say 17 have been blinded through police use of birdshot, and UN Human Rights Commissioner Navi Pillay condemned the government Friday for what she called excessive violence.

"You may have taken away our eyes but you can't take away our voice!" reads a slogan daubed in red paint on a wall.

"The people want another revolution!" and "Ennahda, go away! Game over!" say others.

The revolutionary graffiti recall Sidi Bouzid, the deprived town to the south where a street peddler burned himself to death two years ago in despair at the confiscation of his fruit cart.

His suicide provided the spark for an uprising in Tunisia that spread to Egypt, Libya, Yemen, Syria and Bahrain.

Aware of comparisons between Siliana and Sidi Bouzid, the government temporarily removed the local governor Saturday and promised jobs to victims of the 2010 uprising. Police stopped using birdshot.

"Siliana will be the second Sidi Bouzid; we're going to get rid of these Islamists who know nothing of Islam," Omrani said.

Ennahda was late to respond to the protests, after first accusing leftists who lost last year's elections of fomenting unrest by provoking Tunisians in impoverished areas into confrontations that would drive away foreign investors.

The protests began on Tuesday after a call by the leftist labour union UGTT to take to the streets to demand jobs, investment and the removal of Ennahda's Islamist governor.

Government wrong-footed

The shift to slogans against the Islamists has seemed to wrong-foot the government, which has been absorbed with violent disputes between conservative Salafi Islamists and liberals over the future direction of a once staunchly secular state.

The protests are the fiercest since Salafis attacked the US embassy in Tunis in September over an anti-Islam film made in California, in violence that left four people dead.

They also mirror conflict in Egypt, where secularists have mobilised in recent weeks against post-Arab Spring Islamist rulers whom they accuse of doing little to reform security policies while treating non-Islamists with disdain.

Leftist opponents of Ennahda have been a clear presence on the ground in Siliana, though most protesters seemed to be apolitical youth angry over their economic prospects.

"The government is reproducing the behaviour of Ben Ali's regime," said Iyad Dahmani from the centre-left Republican Party.

"It's an arrogant government that thinks its election victory means it can use tear gas and birdshot on people instead of giving them jobs and investment."

The Western-backed government secured international funding last week for an economy suffering from the financial crisis in the European Union, Tunisia's main trading partner.

Clashes broke out again Saturday between around 3,000 people throwing stones and security forces firing tear gas and live rounds into the air from inside armoured vehicles.

Young men gathered outside the local branch of the UGTT, chanting the revolutionary songs of Sheikh Imam, a famed leftist cleric in 1970s Egypt.

One protester, a teacher who did not wish to be named, said she had voted for Ennahda last year but felt the Islamists had let people down.

"This is the paradise of Ennahda that we elected," she said, grasping an empty tear gas canister. "This is what Ennahda has to offer us. We won't make this mistake again."