The co-founder of file-sharing website The Pirate Bay has been sentenced to two years in prison for hacking into the computers of a firm that administers data for Swedish authorities, and for making illegal online money transfers.

Gottfrid Svartholm Warg has been charged for data breaches against IT firm Logica and Nordea Bank, local media reported.

Warg had been convicted in 2009 of Internet piracy, and was extradited from Cambodia to Sweden in 2012 to begin a one-year jail sentence. He was then charged by authorities in a separate hacking investigation.

"The hacking has been very extensive and technically advanced," Reuters quoted the Nacka district court as saying in a statement. "The attacker has affected very sensitive systems."

Warg has denied the charges.

Prosecutors accused the 28-year-old Warg of successfully transferring 24,200 Danish crowns ($4,300) online and attempting to transfer a further sum of around €683,000 ($915,500).

On Tuesday, a Swedish court ruled that Warg can be extradited to Denmark, where he will face several new hacking charges for downloading a large number of files from a Danish police database.

In Denmark, Warg stands accused of seizing some 4 million files, including the email passwords of 10,000 policemen, personal identification numbers (CPRs) from a driver’s license database and information about wanted persons in the Schengen region. He then allegedly attempted to sell the stolen data for personal profit.

The popular file-sharing website The Pirate Bay was founded in Sweden in 2003. Swedish prosecutors have renewed their attempt to shut down the site, which allows users to download music and movies for free, by filing a motion demanding the seizure of the domain names of both the Swedish and Icelandic Pirate Bay.

In response, the site moved its domain to .sx, which is registered in Sint Maarten, a Dutch territory in the Caribbean.