It's quite obvious that he was mentally disturbed.
The worst thing of all is that I would have felt sorry for him had he not taken this path.
By killing random women, that had no negative history with him, with no remorse, he effectively forfeited his humanity to my reckoning. I have no mercy for him.
And though I do not want to derail this into a gun thread, I think it's worth noting that this mass-murder was planned over a relatively long period of time. His choice of weapon is irrelevant, as I'm quite convinced he would have done it with a knife or other alternative had he not been able to procure a firearm. So let's leave that issue for another day and time.