Microsoft is investigating the recent on-line release of a pirated copy of the forthcoming Xbox "Halo 2" game, warning that downloading the code, or making it available for download, will be treated as theft.

Halo 2 is the sequel to the best selling "Halo: Combat Evolved" game, and is due to go on sale on 9th November.

According to reports, a pirated copy of a European version of the game was released onto the internet late on Wednesday, but is unlikely to have a serious impact on sales because of copy protection mechanisms contained in the Xbox console itself. Unless the Xbox has been illegally modified these will prevent the game being played.

A posting on the web site of Bungie, the games' developer, confirmed the release yesterday, and called on members of the Bungie community to help in the investigation.

"Anyone who has information regarding the leak of the game or individuals or web sites promoting the download of these illegal files is asked to please contact us by sending e-mail to [email protected] or calling 1-800-RULEGIT," says the posting. "We also ask that you help us minimise the spoilers for those opting to wait for the retail release by refraining from posting screens, talking about the story and deleting any such posts you encounter."

Microsoft, which owns Bungie, was blunt in its condemnation of the release.

"We consider downloading this code, or making it available for others to download, as theft. We are currently investigating the source of this leak with the appropriate authorities," said a statement released by the company. "Microsoft takes the integrity of its intellectual property extremely seriously, and we are aggressively pursuing the source of this illegal act."

There are no plans to change the release date of the game, according to reports. This is in contrast to the delay forced on the developers of the equally anticipated "Half-Life 2" game when last October hackers stole portions of the game's source code and posted them on the internet.

The on-line gaming community was furious when the launch date of the game – expected to be last Christmas – was put back until September this year, to allow modifications to be made to the code.

The hackers have since been arrested.

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