German police on Wednesday said three men have been arrested on suspicion of sexually abusing almost two dozen children in the western town of Detmold.

Police said the men abused at least 23 children aged between 4 and 13 over a period of 10 years, but authorities are concerned there may be more victims.

Read more: In light of abuse scandal, Germany steps up child protection

Much of the abuse, which involved producing pornographic material, took place at a campsite where one of the alleged perpetrators permanently lived.

Investigators have obtained 13,000 files containing child pornography, taking up 14 terabytes of data space.

"We still have a lot of work ahead of us," said the head of the investigation, Gunnar Weiss.

The three suspects — aged 33, 48 and 56 — have been detained.

Achim Tietz, another investigator, said the scope of the crimes only became apparent as investigators looked further into the case.

law/rt (AP, dpa)

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