Story highlights More than 1,000 people were protesting outside a far-right political party in Stuttgart

Demonstrators tried to block entrances and things got violent, police said

(CNN) Five hundred people were arrested in Germany after violent clashes broke out, authorities said.

More than 1,000 people were protesting Saturday in Stuttgart, where Alternative for Germany, a far-right political party, is holding a two-day conference over the weekend.

Demonstrators tried to block party members from entering the building where their conference was taking place.

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Protesters then clashed with police, throwing flares and setting tires on fire, according to Richard Leuze, the spokesman for Reutlingen police.

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