My story is in the very, very early stages, but basically demons come through gateways for short periods to earth and wreak havoc, there's a small band of humans with magical ability that fight them, the government do their best to mask their appearances by erasing camera tapes, fobbing off gas explosions etc., but I'm not sure what part of the government would do that, what titles would the staff have etc.? Does anyone have a link to Wikipedia or some other site that could explain that I could read about? Any help is much appreciated, thanks
Okay, I'm going to assume you're not asking which department actually does the demon-hunting. (Cuz I'm pretty sure in reality, we hire and elect otherworldly monsters in the government.) It would probably depend on how long this group has been around, and what their ultimate goal is. If it's something pre-WW1, I would say this would a branch of the military. Started in the mid 20th century? Probably connected to the NSA or the CIA. If it's a recent creation, it's probably run by Homeland Security. You could also place it outside the army or any of the alphabet agencies, make it its own entity. You could even attach it to the Library of Congress, or some other academic institution, as there are probably a lot of academics on your demonbusting squad.
The thing with "secret organizations' is that they are secret. Their inner clockwork, how they function, their P&P etc. is a secret they guard even more than the actual data or information with which they are charged. I worked in the U.S. military intel field during my entire enlistment in the USAF. How data is handled, how it's found, how it's reported, what happens to that data, all of that is something that is a million times more precious than the data itself because the data can, and usually does, age out of importance, but how it's dealt with is forever. When you look at the ongoing Snowden deal, you see a lot of people arguing that, big deal, who didn't think stuff like that was going on. It's not the data itself, it's what the data tells others about the inner workings of the organization that is problematic.