Around 1,700 followers of the PEGIDA movement rallied near the central train station to protest a spate of robberies and sexual assaults against women during New Year’s Eve in the city, which was blamed on refugees by the far right.

Police asked PEGIDA supporters to end their rally after several demonstrators among the group started to attack the police with beer bottles and firecrackers.

During the clashes between the police and some of the protesters, police used pepper spray and water cannon.

The robberies and sexual assaults at Cologne’s central station on New Year’s Eve have sparked security fears in German society about the refugee influx, as far right groups have tried exploiting the incidents to attack government’s open door policy for asylum seekers.

Local media reported this week that around 1,000 men, mostly Arab and North African refugees, divided themselves into smaller groups at Cologne’s central station on New Year’s Eve, sexually harassed women there and stole money and cell phones.

Media have accused police in the city of being ineffective during the events, and amid growing public pressure, Cologne’s police department chief, Wolfgang Albers, was fired by the interior minister.

On Saturday, Cologne police department announced that criminal complaints they received due to the events on New Year’s Eve has increased to 379, and 40 percent of them were sexual assault complaints.

More than a week after the events, the composition of the groups met at Cologne’s central station and their motives remain unclear. Human rights activists have warned against a general suspicion of refugees.

The Interior Ministry said Friday that the federal police had identified 31 suspects, and 18 of them were asylum seekers.

Nine Algerians, eight Moroccans, five Iranians, four Syrians, one Iraqi, one Serbian, one U.S. and two German citizens were among the suspects.

Under growing pressure, German Chancellor Angela Merkel has announced that her government will examine possible legal changes to facilitate the deportation of refugees who are convicted of such crimes.

After a meeting of her party Christian Democratic Union in Mainz, Merkel described the incidents as “disgusting criminal acts” that require a “robust response”.

“Possible legislative changes are in the interest of citizens, but they are also in the interest of big majority of refugees,” she added.

Germany is shouldering the largest part of Europe’s refugee crisis and Chancellor Merkel’s coalition government is facing growing public criticism due to its liberal policy.

The EU’s biggest economy has received a record 1.1 million refugees in 2015, and Syrians were the largest group with 428,000, followed by 154,000 Afghans and 121,000 Iraqis.

The surge in asylum applications in Germany has been exploited by far-right and populist parties that organize weekly rallies against immigration across the country.