I am from Indianapolis, and we haven't heard about this at all. Carmel is a rich suburb of Indianapolis, but I don't think it would be a really strategic target here. Now Newport, which houses the VX stockpiles, well, that would be one I would assume we were guarding closely.
Things like this are not reported, even to local officials, in order to alleviate widespread panic. Due to human nature, it's SOP to take care of things like this in secret, and it's been that way for many, many years. Local authorities are not equipped or trained to deal with this sort of thing in the highly determined manner that federal agencies are, despite what they might like to think.
No, I don't like it either, being as wary of overbearing federal government as much as I am, but that is the way this particular game must be played, if one wants to win at minimum cost, both in lives and material.
This particular brand of secrecy is only getting attention now because it can be used as a means of attack against a politician for whom the democRATs will always harbor an undying hatred. Plus the fact that Islamic terrorism is very much a present-day affair.