If you find this horrifying (and I hope you do, because there can be no moral justification for celebrating murder), then I encourage you to really think about whether we would not be better off without such extremist language poisoning people's minds. We have to try to stop escalating, or the cycle is going to destroy our society.
It is historically proven as the first step to violence. People seem to think that words don't matter.
They matter very much. Just because you can read millions of words a day, doesn't mean they're not powerful.
Support him or no, he didn't deserve to die for his political beliefs.