Cologne police have reportedly launched an investigation into the cops who leaked internal reports of mass harassment and sex assaults on New Year's Eve to the media. The press only learned about the outrageous attacks four days after the incidents.

According to Süddeutsche Zeitung, police recently launched an investigation to find those who had spread the "secret" information without permission. The authorities are determined to find out how internal police reports became public.

"A collection of materials is currently under way, the police are conducting an internal investigation," a spokesman for the Cologne prosecutor’s office told Süddeutsche Zeitung.

‘New form of criminality’: Sex attacks on NYE in 12 German states - leaked police report https://t.co/2eFrb9tl3Spic.twitter.com/kr66uZ2v74 — RT (@RT_com) 25 января 2016

The Cologne police tried to deceive the public until the information from insiders leaked to the media, the Deutsche Wirtschafts Nachrichten (DWN) daily reported. Describing the investigation into the case as an "absurd measure," the newspaper added that the authorities probably have nothing more important to do than search for the whistleblowers. "Without the leaks from the police, the extent of the orgy would not have become known,” it stressed.

According to DWN, the police officer who revealed the real state of affairs during the New Year's Eve celebrations in Cologne has not hurt the police. "The [real] damage has been caused by those who told tales out of opportunistic motives and presented the reality in pictured reality a distorted way. They not only caused the damage to the police, but to the public as well," the article said, adding that the whistleblower who exposed the Cologne attacks is actually a real "hero."

First suspect in Cologne sex assault, 26 yo asylum seeker from Algeria, arrested in Germany https://t.co/rjnM7GNGP6pic.twitter.com/Z4I9A4wIFt — RT (@RT_com) 19 января 2016

Over 1,200 people fell victim to attacks on New Year’s Eve in four German cities, more than a half of them suffering from sexual assaults, State Interior Minister Ralf Jager said in his report to the regional parliament late last month. 30 suspects have been identified by police in relation to this wave of crimes, with 25 suspects coming originally from Morocco and Algeria. According to a leaked federal police report cited by German media, Cologne-style sex attacks and thefts happened on New Year’s Eve in 12 other German states. Local investigators said the assaults represented a “new form of criminality.”

Cologne police chief Wolfgang Albers resigned a week after the incident, while Angle Merkel’s Christian Democratic Union proposed stricter penalties for migrants who committed crime – including speeding up their deportation. After the incidents provoked a new wave of criticism of police and the regional Interior Ministry, Jager said that his ministry only managed to make a real assessment of the situation several days after the attacks took place in Cologne and other cities, due to the growing number of complaints.

“The ministry has nothing to conceal. Everything should be put on the table,” he said, as quoted by the Rheinische Post.

’How to behave with women’ course gone wrong: Refugee teen charged with rape https://t.co/vr7fON7XgSpic.twitter.com/dlXB7tNxhQ — RT (@RT_com) 24 февраля 2016

Germany could let in some 1.5 million refugees this year alone - last year the number stood at 1.1 million. The country is preparing to allocate tens of billions of euros for migrant accommodation, integration and language lessons.

Germany is not the only European country which faced sexual assaults on New Year’s Eve – similar attacks were reported in Austria, Switzerland and Finland.