At least 200 masked far-right supporters, carrying placards with racist overtones, went on a rampage in the eastern German city of Leipzig throwing fireworks, breaking windows and vandalising buildings, police said.
As roughly 2,000 anti-Muslim "LEGIDA" protesters marched peacefully in the city centre on Monday night, police said a separate group of 211 people walked through the southern Connewitz district before setting off fireworks, erecting barricades and vandalising property. The top floor of one building caught fire.
The group carried a placard reading "Leipzig bleibt Helle", or "Leipzig stays light", an apparent reference to the skin colour of residents.
|A hooded man walks past a destroyed shopping window in Leipzig, Germany, 11 January 2016 [Jan Woitas/EPA]
"The 211 people were to a not insignificant degree already on record as being right-wing sympathisers and or members of violent sporting groups," said police, adding that officers brought the situation under control relatively quickly.
The police put the violent protesters in a bus which was then attacked by left-wing supporters.
At the LEGIDA protest, people shouted "Merkel must go" and held placards showing the chancellor in a Muslim veil and reading "Merkel, take your Muslims with you and get lost".
Counter-demonstrators, led by Mayor Burkhard Jung, carried a banner saying "Welcome in Leipzig" and placards saying "No PEGIDA," referring to the nationwide anti-Islam movement.
On Monday, several Pakistanis and Syrians were injured in attacks by gangs of people in Cologne, the German city where hundreds of assaults on women during New Year's celebrations have been reported.
The assaults on women in Cologne and other German cities have prompted more than 600 criminal complaints, with the police investigation focusing on asylum seekers.
The incidents, ranging from theft to sexual molestation, have kicked off a highly charged debate in Germany about Chancellor Angela Merkel's welcoming policy on refugees and migrants, more than one million of whom entered the country last year.
Wenzel Michalski, the Human Rights Watch director in Germany, said that the recent attacks on foreigners in Cologne is exactly what people feared would happen following the sexual assaults on New Year's Eve.
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"Merkel's open-door policy has already been attacked by right-wing politicians and groups. Now this has given them fuel and more proof to feel empowered," he told Al Jazeera.
"On a bigger scale, the Europeans' welcome policy might be in danger because of this incident. Germany is important, where else will they [refugees] go?"
Michalski also said that the German police should take part of the blame because they failed to protect citizens that night and that they should improve security.
Hambar Issa, a Syrian refugee in Berlin, told Al Jazeera that refugees are concerned about a potential backlash after the sex assaults.
"I live with a German family here in Berlin and nothing has changed between us following the events in Cologne.
"But we as refugees here in Berlin have been watching the news and are up to date on the situation. We are all upset about what has happened and we condemn these assaults," Issa said.
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"We are nervous and worried about what might happen next. It is obvious that Syrians are being targeted in response and this scares us.
"Any refugee who commits a crime here in Germany will be punished according to domestic laws; I think this should be made more clear to refugees. I personally think the German police are doing a good and fair job to protect us refugees and German citizens".
Germany registered 1.1 million asylum seekers in 2015, the interior ministry said last week, with refugees from war-torn Syria making up almost 40 percent of arrivals.
The annual arrivals were a record for Europe's biggest economy and around five times more than in 2014.
Additional reporting by Fleur Launspach. Follow her on Twitter @FleurLaunspach
|Participants hold candles and posters reading 'Lepizig shows courage' during a protest against LEGIDA [Fabrizio Bensch/Reuters]
Source: Al Jazeera and agencies