Berlin (CNN) The German government condemned attempts to "spread hatred on the streets" after a violent demonstration Sunday in Chemnitz, eastern Germany, where protesters called for foreigners to leave the city.

Police admitted being unprepared for the scale of the protests, which took place after a 35-year-old man died from injuries sustained in a fight.

Footage posted on social media shows participants clashing with police and shouting "Foreigners get out," "This is our city" and "We are the people," a phrase used 30 years ago to call for the reunification of East and West Germany, but now frequently heard at far-right gatherings to express anti-immigrant sentiment.

In one video, two men are seen chasing after someone they believed was an immigrant.

About 800 people took part in Sunday's protest, police said, with around 50 of them encouraging violence. The demonstration, which took place on the final afternoon of the city's summer festival, was called only a few hours earlier, and police initially did not have enough officers available. Extra officers were called in from the nearby cities of Leipzig and Dresden to deal with the incident.

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