Västerås police were acting on a tip off from the Swedish Anti-Piracy Agency (Svenska Antipiratbyrån -APB), a private copyright advocacy group.

“He was collected for interrogation and after that I took the decision to arrest him. He sat in custody for around a day and has now been released,” district prosecutor Fredrik Ingblad told newspaper Vestmanlands Läns Tidning.

The 33-year-old is believed to be part of a clandestine file sharing network, but there are currently no further suspects.

“We shall have to await the results of the technical investigation. As the case in question concerns a server there could be other file sharers either here in Sweden or abroad, it is too early to tell,” Fredrik Inglad said.

The 33-year-old denies all the allegations and told police under interrogation that he was under the impression that the server contained computer games.

The Anti-Piracy Agency claimed on their website that the server did in fact contain copyrighted material – to the tune of 90 terabytes.

“We regard the man to be one of the leading figures behind the ‘warez scene’ syndicate which is responsible for all pirate copying. The police operation will help to stem the flow of pirated material onto the internet,” said Henrik Pontén, an ABP lawyer.

The APB also added that the man will be served with a demand for compensation, with the amount based on the stock of 10,000 films.