Stockholm - Four men Monday refuted charges that they were accessories in violating copyright law as operators of a popular website that allegedly acts as a hub for illegal file sharing.

Prosecutor Hakan Roswall presented the charges against the four, alleging they helped others "breach copyright laws" and made illegal gains by selling advertisements on the Pirate Bay website.

The Pirate Bay website was temporarily shut down in June 2006 after a police raid, but returned to operation from an unknown location a few days later. Its backers said it was a not-for-profit group that did not store copyrighted material, but only offered a search engine for users who exchange music, films and computer games.

The website has long angered music and movie companies. Of the 33 alleged cases of copyright infringement against it, 20 were related to music and nine to films, including Harry Potter and the Goblet of Fire.

Roswall called for a fine of 1.2 million kronor (147,000 dollars).

He said the site had three components, including an index portal, a catalogue and a tracker function that allowed peer-to-peer networking where files were exchanged.

During his opening statement Roswall presented the technology.

The four - Fredrik Neij, Gottfrid Svartholm Warg, Peter Sunde and Carl Lundstrom - also face a two-year jail term and sizable demands totalling over 100 million kronor for compensation from music and film companies, as well as computer game producers.

Lawyers representing the four said that "ads had only partially financed the site" and rejected the charges and demands for damages.

Interest in the case is high and contributed to public broadcaster SVT's decision to stream audio from the courtroom to the internet during the proceedings. Pirate Bay also offered a link with live blog updates. (dpa)