The Swedish man, Gottfrid Svartholm Warg, 27, has been living in Cambodia for some time.

An appeals court in Sweden sentenced three others behind the site to between four months and 10 months in prison plus fines in 2010.

Warg failed to attend that hearing due to illness and his sentencing was deferred. He had originally been sentenced to a year in prison in 2009.

"We had a request from Sweden to make an arrest as he had committed cyber crime there," police spokesman Kirth Chantharith told Reuters.

"We don't have an extradition treaty with Sweden but there are other ways to do it," he added, without elaborating. Cambodian authorities were waiting for legal documents from Sweden, he said.

A Cambodian website, Khmer440.com, which originally reported Warg's arrest, said he had been living in Phnom Penh for four years.

Swedish subsidiaries of prominent music and film companies had taken Pirate Bay to court claiming damages for lost revenue. Mainstream media firms have also taken steps in other countries to have it blocked.

Pirate Bay, launched in 2003, provides links to other sites where people can download music and films for free.

The group that controls it says no copyrighted material is stored on its servers and no exchange of files actually takes place there so it cannot be held responsible for what material is being exchanged.

(Reporting by Prak Chan Thul; Editing by Alan Raybould and Robert Birsel)

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