I'm heartened, slightly, by a few here who have cooler heads.
I think that the PD would be making a mistake, if their press conference indicated, in all caps (as some here would have it) that there IS A KILLER ON THE LOOSE.
I also think that the PD, even though not every single one of them are mental giants (like any other group of people) have at least some people who are much better at this business, than most of the NDA folk - no offense. I refer to myself too, naturally.
Further, to insinuate that the PD department is staffed by idiots, incompetent, or otherwise not performing up to your standards, because they're not playing their entire hand to the public, shows what little we know.
I do guess that it will be difficult for the killer(s) to hide. It is said that most crimes involve money or passion. Shouldn't be terrible hard to find people with motives.