People who do mass massacre (especially on children) without a reason is very rare compared to other killing types.

But this rare event seems to be happening a lot nowadays. %99 chance there is a hidden agenda behind this which we can't fathom.

Well, these children were definately innocent, and really a reason to mourn to. Unlike to other mass killings of people which we have no clue about, they maybe psychos themselves.
But these children are not.

What we witnessed today is the death of humanity.