"we have no information that suggests that there is any additional threat posed by others related to this incident."
That could mean anything, from "they got the accomplishes" to "there were no accomplishes", to "We don't have a clue, including anyformation indicating that there is *not* any additional threat ...". I tend toward the latter. If they had anything, he'd have said so.
I'm thinking something to the effect someone else already posted like "pay no attention to the man behind the curtain..." Way too much going on, not enough being broadcast. Makes me suspicious. I hope they are developing some good leads, and will let us know when they've finished, but I'm not betting anything I can't afford to lose on it.