OMG! I just heard about this as well. First of all, prayers to all those affected. I cannot even begin to imagine.
I don't understand how anyone ANYONE can do this sort of thing. It makes me sad and angry.
I remember when my son was 11, his school had a lockdown because there a criminal element just down the street and the police were all over the place - the kids were terrified.
Go home and hug your children.