TUNIS (Reuters) - Tunisian demonstrators defied the threat of a security clampdown on Wednesday as they spilled onto the streets of the capital and at least four other towns for a third night of violent protest fuelled by economic hardship.

Police fired teargas to disperse crowds in Tunis and in Tebourba, a small town nearby where one protestor was killed in Monday, witnesses said.

Since starting with one small protest on Sunday - just days before the 7th anniversary of the Arab Spring movement that convulsed North Africa and the Middle East in 2011 - the demonstrations have spread across much of the country.

They spiralled after the government hiked prices of staple goods and introduced new taxes at the start of the year to try to tackle a ballooning deficit and appease foreign lenders.

Late on Tuesday, clashes erupted in more than 20 towns, as protesters attacked police stations and government buildings and torched cars, also hurling petrol bombs at a Jewish school on the southern tourist island of Djerba.

About 50 policemen were wounded in that violence and 237 people were arrested, including two Islamists, said interior ministry spokesman Khelifa Chibani.

“What happened is violence that we cannot accept. The state will remain steadfast,” Prime Minister Youssef Chahed said in a video broadcast by local radio after he visited towns hit by clashes.

While Tunisia is widely seen as the only democratic success story among the Arab Spring nations, it has also had nine governments since then, none of which have been able to deal with growing economic problems.

The 2011 uprising and two major militant attacks in 2015 damaged foreign investment and tourism, which accounts for 8 percent of Tunisia’s economic activity.

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Chahed on Wednesday accused the opposition of fuelling dissent by calling for more protests.

JEWISH SCHOOL ATTACKED

The previous day, petrol bombs were hurled at a Jewish school on the southern tourist island of Djerba, home to an ancient Jewish community.

There were no protests in Djerba itself, but locals said unknown assailants had exploited the fact that there was a reduced security presence as police were busy elsewhere.

“Unknown people took the opportunity of the protests and threw Molotov cocktails into the lobby of (the)... school,” the head of the local Jewish community, Perez Trabelsi, told Reuters.

Jews have lived for over 2,000 years in mainly Muslim Tunisia, where Islamists, secular groups and labour unions have since 2011 argued over what direction the country should take.

Djerba is home to Africa’s oldest synagogue, which was hit by al Qaeda-linked militants in 2002 in a truck bomb attack that killed 21 people including Western tourists.

Among the hundreds arrested on Tuesday were two radical Islamists who had helped storm a police station in Nefza town, the interior ministry spokesman said. In Tunis, a crowd stormed a Carrefour market.

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GROWING ANGER

The protests have drawn in hundreds in each town where they have taken place, though they have been smaller than previous waves of demonstrations since 2011.

But public anger has been building since Jan. 1, when the government raised the price of petrol and other items and hiked social security contributions and taxes on cars, phone calls, internet usage and hotel accommodation.

The Ennahda Islamist party, which governs in a coalition with secularists, called for the minimum monthly wage to be hiked to 357 dinars ($143) and for more aid for poor families, echoing calls by labour unions.

There was no immediate response from the government.

But in a sign that the public coffers are strained, Taoufik Rajhi, minister of economic reforms, told parliament there was no extra money for the health sector, infrastructure or education.

At 15 percent of economic output, the state’s wage bill is one of the highest per capita in the world, and parliament on Tuesday passed a law to offer voluntary redundancy to public service workers as part of plans to trim it to 12.5 percent by 2020.