BELGRADE, Serbia - Serbia's riot police fought running battles on Sunday with hundreds of far-right supporters who tried to disrupt a gay pride march in downtown Belgrade. Several dozen people were hurt, officials said.

The rioters also hurled Molotov cocktails at the headquarters of the ruling pro-Western Democratic Party, setting the garage of the building on fire.

Thousands of police officers sealed off the streets in the capital where the march took place, repeatedly clashing at several locations with rioters who were trying to burst through security cordons.

The protesters, chanting ``death to homosexuals!'' hurled bricks, stones, glass bottles and firecrackers at riot police. Several parked cars and shop windows were damaged and at least one police vehicle was set on fire.

Police fired tear gas and deployed armored vehicles to disperse the charging protesters in the heart of Belgrade even after the brief pride march ended.

Hospital officials said at least 46 people, most of them police officers, were injured. Police said several rioters were arrested.

Right-wing groups say the gay events are contrary to Serbian family and religious values. Most of the rioters Sunday were young football fans whose groups have been infiltrated by neo-Nazi and other extremist organizations.

``These riots obviously have nothing to do with the gay parade or any moral values,'' said Democratic Party spokeswoman Jelana Trivan. ``These are hooligan gangs which must be punished severely.''

Sunday's march was viewed as a major test for Serbia's government, which has launched pro-Western reforms and pledged to protect human rights as it seeks European Union membership.

Right-wing groups broke up a pride march in 2001 and forced the cancellation of last year's event.

Vincent Degert, the head of the EU mission in Serbia, addressed around 1,000 gay activists and their supporters who gathered at a park in downtown Belgrade which was surrounded by riot police, including armored vehicles.

``We are here to celebrate this very important day ... to celebrate the values of tolerance, freedom of expression and assembly,'' Degert told the crowd waving rainbow flags.

The brief 15-minute march ended without violence, with the participants heading into a downtown hall for a party. Some chanted, ``We have succeeded.''

Hospital officials said a group of young men attacked the headquarters of a women's human rights organization early Sunday, injuring one activist. The ``Women in Black'' organization said the men were looking for gays.

The U.S. Embassy in Belgrade said there was a high potential for violence before, during and after the march and strongly recommended that its personnel avoid the downtown area for the day. The same right-wing group set the embassy on fire during riots in 2008 to protest U.S. support for Kosovo's independence.