Police use tear gas to quell new protest in Tunisia (VIDEO)

Police in Tunisia have fired tear gas at anti-government protesters staging a sleep-in outside the prime minister's office as tensions resumed in the capital Tunis, according to reports.

The protest began Sunday, when thousands took to the streets to demand that ministers from the administration of former president Zine El Abidine Ben Ali be kept out of a new government.

Ben Ali fled Tunisia Jan. 14, after 23 years in power, amid unrest over high unemployment, food prices and corruption.

The General Union of Tunisian Workers, known under its French acronym UGTT, has refused to recognize the new government because it keeps in place key figures from Ben Ali's regime, including Prime Minister Mohammed Ghannouchi.

"We support the demands of the people. The UGTT will never abandon the people in their struggle to demolish the old regime," Nabil Haouachi, a representative of the teachers' union within the UGTT, told Agence France-Presse.

Observers believe this week could prove crucial for Ghannouchi’s interim coalition, as it seeks to bring stability to the country. Many Tunisians, however — especially those from rural areas — continue to see it as tainted with the old regime of the fallen president.

Many of the protesters on Sunday had made their way to the capital from the impoverished rural parts of Tunisia where the uprising began and held up pictures of victims of Ben Ali's bloody crackdown in recent weeks.

The movement against Ben Ali began after a 26-year-old fruit vendor, Mohammed Bouazizi, set fire to himself in a protest against police abuses in the impoverished central farming town of Sidi Bouzid.

The Arab world's first popular revolt in recent history has inspired dissidents across the region to call for Tunisia-style protests in Sudan and Yemen.

Many schools stayed closed Monday, despite a government order to re-open, after teachers called an "unlimited" strike in protest against the new cabinet.

The government has said at least 78 people have been killed in the violence.  U.N. officials have said the death toll could be as high as 100.

State media, meanwhile, reported Sunday that Larbi Nasra, the owner of Hannibal TV and a relative of Ben Ali's wife, was arrested on charges of treason.

Also detained were the former presidential spokesman Abdelaziz Ben Dhia and head of the Senate Abdallah Kallel.

Authorities had opened an investigation against the family for plundering the nation's resources through shady dealings, including illegal property acquisitions and currency transfers. Those targeted included Ben Ali, his wife Leila Trabelsi, her brothers and their children, according to an official source quoted by the broadcaster. Last week 33 family members were arrested by authorities, while reports said the former president's wife raided the central bank for gold before fleeing the country.

European Union countries are working to freeze the assets held by Ben Ali's family but want to avoid destabilizing Tunisia's economy in the process, an official said Monday.

An EU diplomat confirmed that the bloc would react by freezing assets connected to the Ben Ali family, as Switzerland did last week.

But he warned that given that the disgraced clan "had [its] hands in many pots," a straightforward freeze on Tunisian companies it controls could have potentially disastrous consequences.

"Imagine if a result, the shelves of the main supermarket chain in the country remained empty," the official said, according to a report.