According to producer Tony Sturtzel from Massive Entertainment, the Hunters are entering the pool of factions now in The Division, as he confirmed during a meeting at PAX West. A concept art was provided together with the low profile announcement, but unluckily we don't have many other information about the role this faction will have throughout the story.
If we had to tell you something about this, we'd surely describe Hunters as something between the heavy armored Last Battalion and fire lover Cleaners, with a good range of weapons (snipers and shotguns seem to be featured, at least) and a lot of tech stuff which we don't think will be just aesthetic.
Hopefully we'll have a further look at this new faction during the livestream slated for September 13, where Ubisoft and Massive Entertainment will detail the 1.4 update coming later this October.
Credits: Special thanks to Epic Slayers for the video.