Suspects sexually abused at least 23 children, aged from 4 to 13, for ten years in the western German state of North Rhine-Westphalia and filmed terabytes of pornographic materials. However, investigators suspect that there might be more victims. Local youth welfare offices are also being investigated.

Three men, a 56-year-old suspect, a 33-year-old and a 48-year-old, considered the head of the group, have been arrested in Germany over suspicions that they abused children and produced child pornography for a decade, police and prosecutors stated during a press conference in the city of Detmold on Wednesday.

The head of the investigative committee, Gunnar Weiss, revealed that there are more than 1,000 individual episodes. The 48-year-old has reportedly filed a partial confession, while the other two men have remained silent. According to the police, the main suspect and the 33-year-old supposedly met in relevant chatrooms on the so-called Darknet around 2008 and arranged everything for their gruesome activities at a campsite near the border with Lower Saxony, where one of them lived.

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The abuse continued over the last ten years. Some 23 children, aged between 4 and 13 years old, from North Rhine-Westphalia and Lower Saxony were assaulted. However, the investigators assume that there are more victims.

"We still have a lot of work to do”, said Weiss.

A 14-terabyte-data volume with 13,000 secured child porn files was handed over to the Federal Criminal Police Office, but the full extent of the deeds became known over the course of the investigation. Not all the seized material investigators analysed was created by the suspects as some of the files had already been flagged by police.

The prosecutor is also investigating youth welfare offices in two districts of Lower Saxony, checking whether the authorities might have “made mistakes”.