Rainbow Six: Siege's first expansion, entitled Operation Black Ice, comes out next month, but now at least some of the content contained in the pack has been leaked (picked up by GamingBolt). The leak details a couple of new weapons, such as the C8-SFW assault rifle or the CAMRS marksman rifle, but more interestingly, the leak also reveals two new Operators called Frost and Buck.
Buck has an underbarrel attachement on his weapon, which allows him to shoot a couple of powerful shotgun shells. Frost on the other hand can put a powerful trap down, which incapacitates enemies.
You can see the screens below, which still have not been validated by Ubisoft, but looks quite legit.

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