Hundreds of left-wing activists have been arrested during a protest against an annual conference held by the far-right anti-refugee Alternative for Germany (AfD) Party in the southern city of Stuttgart.

Stuttgart police said on Twitter that over 500 protesters were briefly taken into custody after clashes erupted during the demonstration, but they were later released “in small groups.”

The arrests were made on Saturday outside the ICS International Congress Center where the AfD event was being held.

The scuffles broke out after riot police used tear gas, pepper spray and water cannon to disperse the demonstrators as they attempted to disrupt the AfD conference.

Many protesters chanted slogans in support of refugees, with one banner reading, “Human rights, not right-wing humans.”

They also shouted “Nazis out,” “Bye, bye AfD,” “No to AfD,” and “No rights for Nazi propaganda.”

The demonstrators blocked roads, burned tires and threw firecrackers.

Police spokesman Lambert Maute said that two policemen were slightly wounded, but no protesters sustained injuries in the clashes.

During Saturday’s conference, AfD members discussed a new anti-Islam manifesto, including a ban on minarets on mosques, the call to prayer and full-face veils for women.

The AfD achieved gains in regional elections last month, claiming almost a quarter of the vote in the German state of Saxony-Anhalt.

The right-wing party campaigns against German Chancellor Angela Merkel’s open-door policy towards refugees.

Germany, one of the most popular destinations for refugees, registered about 1.1 million refugees between January and December 2015. The country is expecting 2.5 million more to arrive over the next five years.

Europe is facing an unprecedented influx of refugees, most of whom are fleeing conflict zones in Africa and the Middle East, particularly Syria.

Many blame major European powers for the unprecedented exodus, saying their policies have led to a surge in terrorism and war in the violence-hit regions, forcing more people out of their homes.