Students lock up Sofia University as part of protests in Bulgaria

After occupying a lecture hall for nearly three weeks, the students declared "total and effective occupation" to demand the government's resignation.

Thousands joined a student march through the city on Sunday.

Unrest over poverty and corruption in the EU's poorest state has continued despite early elections in May.

A Socialist-backed technocratic government was formed under a new Prime Minister, Plamen Oresharski, but has lost support amid allegations of corrupt ties with business groups.

Similar protests of unrest had plagued its predecessor in power, a centre-right minority government led by Boyko Borisov.

Academic business at the university was "brought to a complete halt" as protesters were not allowing either teachers or administrative staff to enter the university, according to the Novinite news agency.

Sit-ins, the agency added, were under way at 15 universities across the country. "We are protesting against poverty and unemployment", a student declaration said, quoted by AFP news agency. "We are protesting before we become beggars with a higher education."

On Sunday, university professors and teachers issued a statement condemning the "lies and 'tycoonisation' of the political and social environment".

President Rosen Plevneliev, who is from Mr Borisov's GERB party, told a French magazine he supported citizens calling for a "moral revolution"

The desperation of many Bulgarians has been brought home by a series of self-immolations since the start of the year. At least nine people have burnt themselves to death, according to Novinite's figures.