Prince has taken legal action against fan websites that print images bearing his likeness.

The veteran rock star's lawyers even asked sites such as housequake.com, princefans.com and prince.org to remove pictures of fans' tattoos featuring the musician's image.

However, all three sites have formed a group called 'Prince Fans United' and are challenging the 'Purple Rain' singer's demands, claiming it infringes their freedom of speech.

The group made a statement on PrinceFansUnited.com saying: "It is our opinion that these threats are not made in an attempt to enforce valid copyright as Prince alleges in his threats, rather we believe they are attempts to stifle all critical commentary about Prince.

"We strongly believe that such actions are in violation of the freedom of speech and should not be allowed.

"The law clearly provides for displaying of images of a celebrity's likeness for newsworthy events or matters that are considered to be public interest. All three websites feel that the photographs and/or likeness displayed on their websites clearly fall within the public interest category."