Tom Petty has followed in the footsteps of fellow musicians Billy Idol and Public Enemy in more than one way.

Each posted new material on the internet in MP3 format, and as of today, they've all had their free offerings removed.

Tom Petty was the latest artist to buck the trend and put the frighteners into the established music industry when he chose to post the ironically-titled new track 'Free Girl Now' on MP3.com, the internet's defacto home to legitimate MP3 files.

'Free Girl Now', from the forthcoming 'Echo' album, was made available on MP3.com March 2, at the request of Petty.

At the time, according to a statement from MP3.Com's Hal Bringman, the track was uploaded with the understanding that it had the music company's "consent to do it."

Apparently not.

It took Warner Bros. little time to decide that offering 'Free Girl Now' as a free download was setting "a bad precedent". 150,000 downloads of the file occured in the time it was on offer.

"Tom Petty has always been very conscientious of his fans and their needs," manager John Diaz told sources.

"Now with the advent of the World Wide Web, Petty wanted to use this medium to thank his fans for their loyalty and give something back with this free copy of 'Free Girl Now'".

Echo, Petty's first album since 1996, is due in stores April 13.