Napster fan: Limp Bizkit singer Fred Durst

Dr Dre and his label, Aftermath Entertainment, sued Napster after the company failed to co-operate with a written request to remove his tracks from its database.

The legal action accuses the company of "building a business based on large-scale piracy",

The service has become wildly popular with students, and many US universities have banned its use after it clogged up their computer networks.

Yale, Indiana, and California universities also banned access to the Napster site after being named in Metallica's lawsuit, which alleges copyright infringement and racketeering.

Trade organisation the Recording Industry Association of America sued Napster in December, claiming that the website promotes piracy and copyright infringement.

Earlier this week, the company announced it was promoting a free tour by the rock band Limp Bizkit, whose singer Fred Durst called the site "an amazing way to market and promote music".

He added: "The internet is here, and the ones trying to fight that are the people who are living by certain standards and practices of the record industry - those are the only people who are scared and threatened."