SOFIA, Bulgaria — An anti-government demonstration in Sofia turned violent Wednesday, with protesters clashing with police and hurling stones and bottles at the Parliament building.

A local hospital said 23 people were injured, including six police officers.

The demonstration started peacefully, with about 2,000 students, farmers and medical workers gathering to protest the government, which they accuse of failing to cope with the economic crisis and tackle widespread corruption.

But shortly after the start, masked youths believed to be nationalists and football hooligans began throwing stones and chunks of ice at police officers and vandalized several police vehicles.

Riot police responded with tear gas and dispersed the crowd. Interior Minister Mihail Mikov said 53 people were arrested.

Many Bulgarians blame the Socialist-led government for the country's woes, which have been greatly exacerbated by the current crisis over Russian gas. The opposition is demanding that the government step down and hold early elections. Parliamentary elections are due this summer.