Activision has launched a teaser site for Call of Duty: Ghosts - the unannounced Call of Duty title leaked by retailers last week.

Visitors to the official Call of Duty website are automatically redirected to the mysterious new site, which asks users to "take [their] place in history on the Call of Duty Mosaic" by submitting a picture of themselves via a Facebook or Twitter account.

Submitted avatars gradually appear to be forming the image of a face mask similar to the one found on the game's leaked box art.

But the cat could already be out the bag: NeoGAF users have already discovered an image of the completed mask (pictured above) in the site's source code.

Call of Duty: Ghosts was leaked by UK retailer Tesco last week, with additional details on the game's new "next-generation" engine accidentally revealed over the weekend.

The game is expected to be formally announced this Wednesday, May 1.