BERLIN: German Chancellor Angela Merkel voiced outrage Tuesday at a series of sexual assaults in the western city of Cologne on New Year’s Eve, saying the perpetrators need to be found as soon as possible.

Merkel called Cologne’s mayor Henriette Reker to express her concern about the assaults, which took place around Cologne’s main train station, next to the city’s famous cathedral.

In a statement, Merkel office said the chancellor called for everything to be done “to find the perpetrators as quickly and comprehensively as possible and to punish them without regard to their origin or background.”

“We don’t currently have any suspects, so we don’t know who the perpetrators were,” Cologne’s police chief Wolfgang Albers told reporters. “All we know is that the police at the scene perceived that it was mostly young men aged 18 to 35 ... .”

Cologne’s mayor also cautioned against hasty conclusions about the perpetrators. “It’s completely improper ... to link a group that appeared to come from North Africa with the refugees,” Reker said.

Police say dozens of women reported being sexually assaulted and robbed during the night from Thursday to Friday. At least 90 criminal complaints have been filed, including one allegation of rape. Albers expressed regret that initial police reports of the New Year’s festivities contained no mention of the assaults.

“The full extent of the assaults, particularly the sexual assaults, only became apparent to us the following day,” he said. Separately, police in the northern city of Hamburg appealed for witnesses who observed similar sexual assaults and thefts in the St. Pauli district.