his motivation, clearly we'll know more granularly, but his motivation was to send a macro message. >> rose: has there been any message that might have set him off? >> that will come forensically by interviewing neighbors and family members. law enforcement hasn't really spoken about going to florida where he's from and interviewing co-workers and neighbors there. he's just recently moved to nevada over the last year or two, i believe. so, you know, we really forensically need to peel this onion back and see what it looks like and we haven't done it yet. that information will come from those interviews. >> rose: a remarkable thing, too, are the incredible stories of brave rithat are coming and continue to come of people literally sacrificing their life to save someone. you're hearing that even today, i assume. >> one of the things that has struck me is covering a number of these mass shooting incidences that you kind of go down with a sense of dread in your soul about your seeing the worst of humanity and for the reasons that we've just been hearing about what could lead someone to do