The loon of the year

Well here go again, another senseless crime against humanity. By a person know by many to be unstable. Yet he was able to purchase a gun, and use it against our society, an act that will surely bring more contols against guns. Yes, a gun is an easy way to wreck havoc in a split second. So it is usually the choice of the warped, and criminals, who live among us. My question to everyone out there, when we know someone is unstable, what should our response be. To ignore, because we may hurt someones feelings, or step up and maybe save someones life.