The trial of four German men charged with operating child pornography platform Elysium opened on Wednesday in the western city of Limburg.

The darknet platform was considered one of the largest of its kind, with more than 100,000 registered members in 2017 before it was taken offline.

The main details:

The four men are accused of programming, administering and moderating the Elysium platform.

The defendants lived in the German states of Hesse, Bavaria and Baden-Württemberg while operating the platform. Their ages range from 40 to 62.

Three of the men face up to 10 years in prison, while the oldest defendant potentially faces an even longer sentence for abusing two children ages four and six.

At least 16 people were arrested last year in Germany and Austria in connection to the platform.

Tens of thousands of users exchanged photos and videos of "serious" child abuse

Massive platform: The platform was used to exchange illegal videos and photos between its 111,000 registered users. It hosted recordings of the "most serious sexual abuse." A majority of the users were based in Germany and Austria.

Not just porn: According to German prosecutors, Elysium users also used the platform to arrange meetings to sexually abuse children.

Short-lived sequel: German investigators believe Elysium may have been a copy of a US-based child pornography platform that authorities raided in 2016. Later that year, Elysium started operations and was taken down by summer 2017.

Read more: Darknet, the shady internet

Challenges ahead: The trial is the first against German suspects accused of using the darknet to operate an online child pornography platform.

The Federal Criminal Policy Agency (BKA) has expressed concerns that current data retention rules impede investigations and prevent law enforcement agencies from tracking down more perpetrators. Under current rules, much of the data needed by law enforcement is deleted before they can follow up.

Later this year, Germany's Constitutional Court is set to rule on whether telecommunications companies can retain more data for longer periods, similar to US practices — up to ten weeks in this case.

The BKA hopes that by extending the time for which data, such as IP addresses, is stored by telecommunications companies, they can better chase down leads.

ls/rt (dpa, AP, Reuters)

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