SOFIA, Bulgaria — Angry students chained and padlocked the doors to Bulgaria's largest university in Sofia Monday, demanding the resignation of the embattled Socialist-backed government, an AFP photographer witnessed.

"We declare total and effective occupation," the students announced on their Facebook page, amid efforts to reignite the mass anti-poverty and anti-corruption protests that swept the country earlier this year.

A small group of protesters has occupied Sofia University's main building for 19 days now, prompting the university to cancel all lectures, although students, professors, and staff were still allowed to enter the building.

The students are calling for the resignation of Prime Minister Plamen Oresharski's government, new elections, and an end to perceived widespread corruption in politics.

On Sunday, they received backing from the street, as about 4,000 people demonstrated against the government along Sofia's boulevards, carrying banners that read "Down with the mafia," and "We stay, you emigrate."

The European Union's poorest member state has been rocked by mass anti-government unrest since February, but the demonstrations had subsided in recent months.

Oresharski's technocrat government only came to power in May after the previous cabinet was forced out by the protests, but it quickly fell out of grace for its perceived oligarchic tendencies.

"We do not want lies, unscrupulousness and corruption," Ivaylo Dinev, one of the organizers of the student protest, told demonstrators Sunday.

"We are the voices that say that this cannot go on any more, that this is intolerable. We say: 'Enough'," he added.

Teachers, actors, and intellectuals have backed the Sofia University protest, as well as students across the country, who have blockaded auditoriums in at least 18 other universities.