Second Life is being investigated by German police following allegations that some members are trading child abuse images in the online world.
The investigation follows a report by a German TV news programme which uncovered the trading group and members who pay for sex with virtual children.
The police are now trying to identify the Second Life members involved.
Linden Lab, the creator of Second Life, said it would help identify users and pass on details to prosecutors.
Second Life, as its name implies, is a virtual world in which members create an avatar and then use that character to live out a separate existence.
The investigation was carried out by Nick Schader from the Report Mainz news programme who is also a member of Second Life.
Mr Schader was asked to pay to attend meetings where virtual and real child pornography was being shown.
Members of this group also offered to put him in touch with traders of real child pornography.
The investigation also uncovered so called "age play" groups that revolve around the abuse of virtual children.
Information gathered during the report was passed to the prosecutor's office in Halle who said it hoped to track down the German Second Life user who shared the images of virtual child pornography.
Peter Vogt, the prosecutor in the Halle, told the Deutsche Presse-Agentur agency: "I assume we are going to catch this user fairly quickly."
Under Germany law possession of "virtual" child pornography is punishable by up to three years in jail.