Halo: Reach has reportedly been leaked to public filesharing sites nearly a month ahead of its official September 14 launch date.
The game was recently made available on Microsoft's Xbox Live Marketplace store for review purposes, but a group of modders claims to have bypassed security measures to download and play the title, IGN reports.
While the group in question said that it didn’t intend to distribute the title, further online reports claim it is now publicly available to download from BitTorrent sites.
"We are aware of claims being made regarding a security exploit related to Halo: Reach and are aggressively investigating the matter,” publisher Microsoft said in a statement.
Halo: Reach developer Bungie also commented on the situation in a bid to discourage story spoilers being released ahead of the game’s release.
"Posting to Discuss, Request, or Link To information or campaign spoilers from illegitimately obtained sources -- including illegitimately obtained copies of Halo: Reach -- before the game is officially released will be considered a leak and will be treated as such," the studio said.
"The moderation team is doing their best, but if you want to stay 100% spoiler free, our best advice is to 'go dark' by staying off all internet gaming forums until you have played through the game!"
A pirated version of 2007’s Halo 3 also hit the web a week ahead of the game’s release.