What appears to be the entire code for Bungie's Halo Reach game has turned up on a number of file sharing sites.

The hotly-anticipated multi-player shooter had been hosted on a private area of the Microsoft Live site in order for journalists to preview the release, but Microsoft has admitted that a security breach has meant that pirates have been able to bypass personal download codes given to writers.

Disk images of the game are now appearing on a number of public torrent and P2P sites as well as on popular NZB aggregators and Usenet binaries newsgroups.

As Halo Reach is primarily an on-line multi-player affair, and turning up on Xbox servers brandishing a copy of the illegally-obtained game will almost certainly earn you a life-time ban, we can't see that this particular leak will do too much damage.

It is, of course, rather embarrassing for Microsoft who allowed the leak and Bungie who will be fighting a losing battle to keep plot spoilers from flooding the Internet before the game's official launch on September 14th.