Police used pepper spray and batons on Saturday to halt a large group of protesters attempting to breach a cordon in Essen, western Germany, where a two-day congress by the far-right Alternative for Germany (AfD) party is underway.
It remains unclear if any demonstrators were injured in the 5:45 am incident, but police reported several arrests and attacks on officers.
Authorities urged protesters to avoid violence and disruptive behavior.
An estimated 100,000 protesters are expected to participate in demonstrations against the anti-immigration AfD, which has been gaining traction, particularly in former communist East Germany.
While organizers promised peaceful protests, police expressed concerns about potential violence from around 1,000 leftist extremists planning to demonstrate.
Approximately 600 AfD delegates are meeting in an indoor arena, with party co-leaders Alice Weidel and Tino Chrupalla seeking re-election ahead of next year’s German parliamentary elections.
Several hundred protesters blocked a motorway exit ramp and occupied streets near the congress venue in an attempt to hinder delegates.
Addressing the meeting, Weidel criticized the protests as undemocratic and asserted the party’s resolve to continue.
Several thousand police officers were deployed to ensure security, with a major demonstration scheduled to start at 10 am at the main train station.
On Friday evening, 5,000 protesters gathered for a music rally themed “Bass against hate.”
Some AfD politicians reported being escorted by police from their hotels to the venue, while others managed to reach the arena without incident.
The AfD is under surveillance by Germany’s domestic intelligence agency as a suspected right-wing extremist group, due to concerns over its racist, antisemitic, and anti-democratic tendencies.
Despite controversies, the party secured second place nationwide in the recent European Parliament elections and first place in the five former communist eastern states.
It is projected to emerge as the strongest party in September elections in Saxony, Thuringia, and Brandenburg, raising fears of potential coalition challenges for other political parties.