The Czech Republic's president marked the 26th anniversary of the Velvet Revolution by addressing a rally of his supporters organized by an anti-Muslim group.
Amid heavy security, the Bloc against Islam rallied Tuesday in support of President Milos Zeman, who is known for his anti-Islam rhetoric. Zeman told the crowd of several thousand that they aren't extremists.
Riot police separated them from a counter-demonstration.
The rally took place at a university campus where the anti-Communist revolution began in 1989, prompting Charles University officials to distance themselves from it.
The migrant crisis and the Paris attacks attracted thousands of people to different rallies in Prague in favor and against refugees, even though the country has seen only a small number of asylum-seekers compared to other European nations.
Later in the day, protesters from several anti-immigration rallies joined forces and marched to the government building. They demanded the center-left government resign over its acceptance of a European Union plan to redistribute 120,000 refugees in member states despite its disagreement with it.
Police used force to disperse the crowd of almost 1,000, which included members of the far right, when they refused to disperse. Police spokesman Tomas Hulan said up to 10 protesters were detained.