Clashes between police and protesters outside the Bulgarian parliament Wednesday left 33 people injured, including 12 police officers, medical and government sources said.
Sofia's national medical co-ordination centre told AFP that 33 people with various injuries had been taken to hospitals around the capital -- 12 of them were police officers, said an interior ministry statement.
Police also made 154 arrests, including a 15-year-old boy caught in possession of three home-made bombs, said the ministry.
About a thousand anti-government demonstrators rallied in front of parliament with a similar number of police officers also present, said an AFP photographer on the scene.
The protesters were calling on the government to resign for corruption and inefficiency.
While the demonstration started peacefully, masked nationalists and football fans started throwing snowballs and stones at police officers guarding the parliament building.
They tried to break through the police cordon, throwing bits of fencing at the officers, who were armed with shields and tear gas.
Officers moved in to break up the protest an hour into the demonstration following an anonymous tip-off that protestors were planning to detonate a home-made bomb, said the ministry statement.
National radio quoted eyewitnesses as saying that rubber bullets were fired at protestors during efforts to disperse the crowd.
Shop windows were smashed, cars were damaged and benches overturned as angry youths ran riot in the streets.
The events came exactly 12 years after a similar anti-government rally in January 1997, where more than 10,000 protestors demonstrated outside parliament.
There were also serious clashes between police and demonstrators at the time, leaving more than 200 people injured and the parliament building set on fire.
In 1997, Bulgaria was facing a grave economic crisis and the rally triggered the fall of the then-government, which was the country's last Socialist administration until the current cabinet of Socialist premier Sergey Stanishev was elected in 2005.
Parliamentary chairman Georgy Pirinski expressed concern that tension might escalate and the events of 1997 could be repeated.
Deputy premier Ivaylo Kalfin condemned the violence, but said he fully backed police in their efforts to keep law and order.
