Well on the face of it he must not have been saved, because if he had been he wouldn't have done what he did. Now, are you saying that if he was saved (according to your determination of how one is actually saved), that he could kill 2 people and avoid Hell? Please explain.
The perp's actions certainly point to his not being saved, but only he and God know for sure. 1 Cor. 10:12 says, "Wherefore, let him who thinketh he standeth take heed, lest he fall." To me, that verse infers that I'm capable of the most heinous sin, other than rejection of salvation (settled almost 50 years ago), and to think otherwise opens me to prideful failure.
And to kyredneck: True statement, though someone with such murderous intent probably would've removed the plug, unless he was so mad that he forgot. Nevertheless, when one (or one's friends) are being shot at, one doesn't wait to hear "click" before neutralizing the threat.