Right-wing extremists hurled petrol bombs at Serb police, torched the ruling party’s offices and stoned the headquarters of state television yesterday in pitch battles on the sidelines of a Gay Pride march.

Dozens of people were injured in the violence as protestors, dressed mainly in black and with hooded tops, hurled rocks and molotov cocktails at security forces trying to ensure Belgrade’s second-ever Gay Pride event could go ahead.

At one point, rioters managed to set fire to the headquarters of President Boris Tadic’s Democratic Party (DS) to protest against his support for the march. The building caught fire but the flames were quickly put out and no one was hurt.

Police retaliated by firing tear gas and deploying several armoured vehicles in a bid to keep the protestors away from the parade.

The central Terazije Square was littered with rocks and debris from the protest, with most of the violence erupting after the march had ended.

Local hospital services said at least 57 people were wounded – 10 civilians and 47 police officers.

Unconfirmed reports said several dozen people were also detained during the incidents.

The Serb government condemned what it described as “hooligan violence”.

“No one can violate public order and destroy public property without punishment,” the government said, warning that “all participants and organisers of violence in the streets of Belgrade will be brought to justice.”

A spokesman for the public prosecutor’s office said the state would seek “the toughest possible sentences” against those behind the violence.

Rioters also stoned the building of the Socialist Party of Serbia of Interior Minister Ivica Dacic, but no one was injured. Several windows at the state television RTS were also broken.

Groups of hooligans broke into several shops in central Belgrade, stealing goods before police units detained them.