Authorities in Germany are calling for calm after an official report found most of the men suspected of attacking women in Cologne on New Year's Eve were recent arrivals.
The German interior minister has urged people not to let the incident lead to a general suspicion of refugees and migrants.
It comes amid fears of reprisal attacks as at least four foreign men were attacked by gangs in the city.
Brianna Roberts reports.
A night of violence allegedly perpetrated by around 1,000 men is having far-reaching implications in Germany.
Reports of assaults on women in Cologne on New Year's Eve, ranging from theft to sexual molestation, have prompted more than 500 criminal complaints.
An official report has found the men suspected of being involved in the attacks were mainly from migrant backgrounds.
Of the 19 people under investigation so far, ten are asylum seekers and the remaining nine arrived in Germany after September 2015.
State Interior Minister Ralf Jaeger has acknowledged mistakes were made on the night of the violence.
"It was not the mistake of the officers on duty but police authorities, given the situation, should have asked for additional forces who were available on the night of New Year's Eve. This did not happen at a time when a situation developed which would have required it."
The report's findings are set to add fresh fuel to rising anti-migrant sentiment and criticism of Chancellor Angela Merkel's open door policy on refugees and migrants.
At the weekend, riot police were called to disperse anti-migrant protesters who gathered in Cologne.
And there are concerns anti-migrant sentiments are turning violent.
A group of around 20 men are believed to be behind attacks targeting foreigners in Cologne on Sunday.
Six Pakistanis, two Syrian men and three men from Guinea were among those attacked.
Cologne Police Detective Superintendent Norbert Wagner says police are investigating whether the attacks were coordinated on social media..
"As the situation is right now, we know of four crimes committed in the city centre last night where people of non-German origin became victims of physical violence."
Cologne Police Operations Manager, Michael Temme, says he's concerned by reports of a Facebook page urging Germans to join a "manhunt" for foreigners.
He says such misguided attempts at vigilante justice will not be tolerated.
"We will do everything we can to clearly show the limits to potential criminals and those who think they can take the law into their own hands."
German Interior Minister Thomas de Maiziere has also called for calm.
"When asylum seekers are being insulted as 'cattle', when they or their refugee shelters are being set on fire, when politicians in charge in this country are being called Germany-abolishers or libelled as traitors, when the media is defamed as 'lying press' or when asylum seekers call women crossing the street whores - all this is absolutely unacceptable."
German authorities have set up a joint federal and state investigation to examine the phenomenon of mob attacks on women, and how to prevent them.