Tom Clancy's Rainbow 6: Patriots has been pulled from the database of US retailer GameStop, with all existing preorders being cancelled.
Speaking to IGN, a source said that the US retailer "actively flipped a switch" to remove Rainbow 6: Patriots from its systems.
The source continued by saying that the retailer does not remove games from major publishers without official confirmation that the title has been cancelled.
A GameStop spokesperson told GameSpot that the retailer has "stopped taking reservations as we wait to hear further from Ubisoft on an official release date for Rainbow 6: Patriots."
When asked about the possible cancellation of the title, a Ubisoft representative added that "we have nothing further to share about Rainbow 6: Patriots at this time."
At time of writing, no other major retailer has pulled the game from its listings.
Officially, Rainbow 6: Patriots is due to be released in 2013 for Xbox 360, PlayStation 3, and PC, though Ubisoft CEO Yves Guillemot said in November 2012 that there is a "good chance" the game will be released for next-generation consoles.