There have been two deadly shooting this week, the other at a shopping mall in Oregon.
This is the kind of thing that always puts the profilers who study the offender characteristics of these shooters on alert.
They're worried about what they call the Werther Effect. It's a copy-cat mechanism and they say their studies show it's particularly powerful on adolescents.
So in a case where you'll see someone commit suicide in a high school, it's not unusual to see two or three more in a cycle like that.
What they believe is it's entirely possible that the Oregon incident most of us found disturbing and troubling, an individual like this might have found that challenging to not just imitate it but to go forward with this plan.
They also observed that the fact he killed his mother and then went about the other crimes - CBS News believes he killed his mother at the house - shows that this was planned out from the beginning. This was a calculated crime.
We tend to think of these offenders as being crazy. It doesn't mean they're not disturbed, but they are rational enough to act out these plans, even under tremendous pressure and during the chaos of their own actions.