Syco is working with the IFPI and the police to investigate the leak of unreleased songs including a new Leona Lewis track, "Don't Let Me Down," a collaboration with Justin Timberlake.

Lewis, the 2006 winner of the U.K. TV talent show "The X Factor," is set to release her second album in Q4 via Syco - Simon Cowell's label in partnership with Sony Music Entertainment - and J Records in the U.S.

According to a report in the Sun, the demo track was stolen from Syco's servers by hackers and has since leaked online. The paper said the ballad was being considered as her comeback single.

A Syco spokesperson said the track-listing for the album and the single release schedule are not yet confirmed.

"Don't Let Me Down" was produced by Timbaland and Justin Timberlake, who also provides vocals. It is currently being streamed on some music blogs and it is understood to have appeared on file-sharing networks.

It is believed that a number of tracks from Lewis and 2008 "X Factor" winner Alexandra Burke have leaked and that Syco is treating this targeted theft as a far more serious threat to its artists - and the whole industry - than previous leaks.

The IFPI has always stressed that the appearance of new music on P2P networks ahead of the official release is the most damaging aspect of file-sharing.

"IFPI is working with Syco and law enforcement agencies in the U.S. and Europe to trace the individuals who stole the Leona Lewis/Justin Timberlake track," said Jeremy Banks, head of IFPI's Internet anti-piracy unit.

"The police investigation is ongoing. Such pre-release leaks, however they are sourced, are highly damaging to our members who invest considerable budgets in marketing and promoting music ahead of release. We work closely with all our members to minimize the damage from such leaks and are actively monitoring and removing illegal copies of this track from the Internet to minimise the disruption caused by the leak."

"Syco are working alongside the International Federation of the Phonographic Industry, the British Phonographic Industry, the police and investigators in this and they are making fast progress," said a statement from Syco. "We will certainly look to bring charges against those who are responsible. We cannot give any more details at this stage for operational reasons."