Hundreds of protesters were arrested and briefly detained by German riot police outside a congress meeting for Germany’s anti-immigration Alternative for Germany (AfD) party on Saturday.

Clashes broke out between left-wing activists and AfD delegates as the protesters tried to disrupt the beginning of the party’s weekend congress in Stuttgart and block access to the conference. Protesters were seen lighting tires and throwing firecrackers at AfD members and police.

“No rights for Nazi propaganda,” one protester was heard to yell.

Clashes, arrests as protesters seek to disrupt German right-wing congress https://t.co/Nljk2puij4 — Megan Johnson (@megan4562010) April 30, 2016

Heavily armored riot police used pepper spray to subdue and hold off demonstrators, many of whom were dressed in black and covering their faces. Police also helped to safely escort many of the 2,400 AfD members who are expected to attend the congress into the hall where the conference is being held.

The disruption delayed the opening of the congress over an hour. According to police spokesman Lambert Maute, there were no injuries reported, and “only some minor incidents of eye irritation due to the pepper spray.”

The AfD congress is expected to espouse a hardline anti-Islamic manifesto this weekend, which, along with the statement made last week by European parliament member and AfD deputy leader Beatrix von Storch that Islam is a “political ideology that is incompatible with the German constitution,” has been a recent source of anger and controversy for many Germans.

400 arrests outside German far-right AfD party congress https://t.co/YcEzg80b2L pic.twitter.com/z6XgfzaeQv — The Local Germany (@TheLocalGermany) April 30, 2016

After only three years since its formation, the Alternative for Germany party has now been polling at around 14 percent, and is hoping to ride a series of state election wins to gain entry into the Federal Parliament in 2017. Its policies have been shifting further to the right since its foundation, with its primary platform now revolving around anti-Islamic sentiment and opposition to Chancellor Angela Merkel’s liberal immigration policy.

Merkel has also angered AfD supporters with her public support of Germany’s 4 million Muslims and her statement that “Islam is part of Germany.”

The AfD congress is expected to call for the eradication of many Islamic cultural symbols in German public life, including bans on minarets on mosques, the call to prayer, and face veils on women.

According to Timo Lochocki of the German Marshall Fund in Berlin, the AfD has a long road ahead if it plans on using anti-immigration sentiment to rally support in Germany. Discontent is low there compared to other European nations, since employment is still very high and there remains an overall trust in the government. Historically, such demagogic tactics are only reliable when there’s high discontent in a nation, as was the case with Hitler’s rise to power in post-World War I Germany.

There has been plenty of comparison between the AfD’s position toward Muslims and that of the Nazis toward Jews in the controversy surrounding the party. Aiman Mazyek, chairman of the Central Council of Muslims in Germany, has said that this is “the first time since Hitler’s Germany that there is a party which discredits and existentially threatens an entire religious community.”

Germany: 400 arrested at protest against AfD congress: German riot police have arrested around 400 protesters... https://t.co/RwcfXIRYI4 — Refugee News (@IntRefugeenews) April 30, 2016

Stuttgart police reported on Twitter that more than 500 people had been taken into custody and were later released “in small groups.” More than a thousand riot police were deployed in the conflict. The department added in a statement that three officers were lightly wounded in the scuffles which went on for hours, but there were no reports of injuries among the demonstrators.

[Photo by Carsten Koall/Getty Images]