The internet is abuzz with reports from Xbox 360 owners claiming they've had their Achievements reset to zero.
UPDATE: Microsoft support has said those experiencing Gamerscore issues should sign out and then back into your profile to resolve the issue.
Microsoft's Xbox Support has been inundated with users complaining about years worth of Achievements vanishing in an instant, and it's assured players it is "looking into the issue".
While the problem is likely to be a temporary glitch, given how large the Achievement hunting community is there's sure to be a few livid gamers out there. If it turns out to be permanent we'd advise stocking up on supplies quickly and getting to your bunker. It's not going to be pretty.
Yesterday the platform holder revealed plans to raise the standard gamerscore cap on Xbox Live Arcade titles from the current 200 to 400 effective from April 1.
We'll let you know when Microsoft's got more to say on this.