Hundreds of people have protested in the German city of Cologne over sexual assaults and thefts carried out by groups of men on New Year’s Eve.
Some held up signs demanding action from Chancellor Angela Merkel.
Mrs Merkel has expressed outrage over the “disgusting attacks” and said everything must be done to find those responsible.
Witnesses and police said that the men involved were of Arab or North African appearance.
Political leaders have warned Germans not to link the violence to the influx of more than one million refugees and migrants in the past year.
“It’s completely improper… to link a group that appeared to come from North Africa with the refugees,” Cologne Mayor Henriette Reker said, following talks with police.
Interior Minister Thomas de Maiziere agreed there should not be any general suspicion towards refugees at least “at this stage of the investigation”.
“But if North Africans were the perpetrators, for which there is some indication, there should not be a taboo and people should not gloss over it.”
The scale of the attacks, involving groups of drunk and aggressive young men, has shocked the country.
There is an intense debate in Germany about refugees and migrants who arrived in record numbers last year, many of them fleeing the conflict in Syria.
Women have made at least 90 criminal complaints to police about harassment by gangs at Cologne’s main railway station on Thursday night.
At least one woman in Cologne was reportedly raped and many were groped, including a volunteer policewoman.
Women were also targeted in Hamburg and Stuttgart in similar attacks, but on a smaller scale.
Read more: BBC