Swedish police raided several addresses this morning, including an ISP linked to Wikileaks, while assisting a Belgian file-sharing probe.
Four Swedish nationals were arrested following raids on residential addresses, Umea University and two ISPs.
Computers and servers were seized but police stressed the investigation was centred on specific IP addresses.
Although one raid was on PRQ - a Wikileaks ISP - a spokesman for the Swedish police's copyright unit, Paul Pintér, said the raids had nothing to do with the site.
Pinter told The Local the raids were the culmination of a four-year investigation into a film sharing network called "The Scene".
Leaders of the group get "credz" points for first seeding films onto the network. The next layer down is described as "topsites" and is spread around several IT firms and is where the copyrighted material is held, the paper reports.
Swedish police said evidence would be sent to Belgium for investigation but did not rule out charges for breaches of Swedish law too. ®