Anti-government protesters clash with police
Anti-government protesters at a rally in the Bulgarian capital Sofia have clashed with police outside the parliament building.
More than 2,000 people had been taking part in a peaceful rally when what the police described as a riot broke out.
The rally involving students, farmers and activists was to protest about continued corruption and poverty.
Bulgaria is rated as the most corrupt of the EU's 27 member states by Transparency International.
Shouting "resign!" and "mafia!" the protesters threw bottles, smashed windows on the parliament building, and damaged police cars.
When an anonymous bomb threat was received, the Deputy Mayor of Sofia, Yulya Nenkova, issued an order to break up the rally, local media reported.
The police then used force to disperse the protesters, who were demanding the resignation of the Socialist-led government.
In a statement, the protest organisers accused the government of failing to tackle widespread graft and crime as well as persistent poverty.
Bulgaria has been hit particularly hard this month by the dispute between Russia and Ukraine over gas exports, with some Bulgarians blaming the government for not doing more to shore up the country's energy security.
Press reports have surfaced suggesting the government was warned by the Russians in mid-December that there could be a disruption in gas supplies, yet no action appears to have been taken.
"We are fed up with living in the poorest and most corrupt country," the protest organisers said.
"This a unique protest which unites the people in their wish for change and their wish to live in a normal European country."
Last year the European Commission stripped Bulgaria of 220m euros (£188m) in EU funding over its failure to tackle corruption and organised crime.
The unprecedented move was meant to show that the European Commission was not squandering taxpayers' money, and to warn new and potential EU members that they have to crack down on entrenched corruption.
Bulgarian prosecutors are investigating some 80 cases of embezzlement, but no senior official has been convicted for corruption and more than 100 mafia-style killings remain unpunished.