Halo 4 has apparently been leaked quite a few weeks ahead of its official November 6 release and Microsoft has confirmed that it's investigating the reports in cooperation with law enforcement agencies.
Halo 4 is scheduled to appear at the beginning of November but already images of the game's two discs as well as screenshots of Xbox 360 dashboards with the title ready to be played have surfaced on the web, via Joystiq.
While it's unclear if these images are fake or that people just managed to get early copies of the game, Microsoft has confirmed that it's investigating all the reports.
"We have seen the reports of Halo 4 content being propped on the Web and are working closely with our security teams and law enforcement to address the situation," a Microsoft spokesperson said.
What's more, actual gameplay videos have surfaced on YouTube showing off footage from the first-person shooter, so it's pretty much certain that valid copies of Halo 4 are currently in the wild.
Expect to hear more about these reports as they develop.