An official report confirmed that migrants were involved in the assaults targeting women, which occurred on New Year's Eve in the German city of Cologne.

According to the report, which was presented by the interior minister of the state of Rhine-Westphalia on Monday, the majority of the suspects were of migrant origin, being mainly North African and Arab.

The police in Cologne is accused of making serious mistakes by not calling reinforcements on the night and in the way it disseminated information to the public in the aftermath of the incident.

So far, more than 500 complaints have been filed with the police, with 40 % of them alleging sexual assault.

Nineteen suspects are under investigation by state police in connection with the attacks, none of them being of German origin.

Among the nineteen suspects, there are fourteen men from Morocco and Algeria.

Ten of the suspects are asylum-seekers, with nine of them having arrived in Germany after September 2015, Deutsche Welle reports.

The remaining nine suspects are believed to have entered Germany illegally.

On New Year's Eve, around a thousand men gathered into smaller groups and surrounded women, threatening and attacking them in central Cologne, in the area of the cathedral and the main railway station.

The reports of the assaults have resulted in anti-migrant protests and attacks on foreigners over the weekend, which have been condemned by German authorities.

Similar assaults on women are reported to have occurred on New Year's Eve in other parts of Germany, including Hamburg, as well as in cities across Europe, such as Zurich, Salzburg and Helsinki.