Police arrested ten men aged 22 to 60 and one 53-year-old woman on Saturday evening in Saxony-Anhalt on suspicion of being core members of a paedophile ring. All have been questioned and released as no charges have been filed against them yet.
Magdeburg police spokesman Holger Herrmann told reporters on Monday the suspects were accused of owning and distributing child pornography, in addition to the ring's other alleged criminal activity.
They used a five-year-old to attempt to make contact with other children at a playpark, police said on Monday.
Despite the group being "extremely discreet and careful", investigators discovered it met once a year to exchange contacts and plan alleged illegal acts.
Officers made the arrests after a raid on the group's annual gathering at the town of Aschersleben, police in the central Saxony-Anhalt region said on Sunday.
Saturday's raid involved around 150 officers and 20 vehicles.
The alleged ringleaders come from Berlin, Dresden, Leipzig, North Rhine-Westphalia and Switzerland, and three of them have previous convictions for related offences.
The group is believed to have mainly conducted its activities online after investigators seized computers, communications equipment and hard drives belonging to the suspects.
Rainier Wendt, chairman of the German Police Union, told Bild newspaper he saw the arrests as a great success.
"The detectives must be pretty expert, because investigating on the web is no easy task," he said.
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