Hang all three by the neck until they are dead. Do not use the hangman noose, because we do not want the neck to break immediately. No, make them suffer suffocation until lights out. Burning someone alive is a torture, and so the torturers should suffer greatly for what they did.
I hope they find them. I also know there are other people who probably know who did it, and I hope they pass that info on to the police. No snitch shyt only helps the criminals causing havoc in the community, it does not help the normal everyday people just trying to live our lives.
Edit: As for the OP, did you forget that something similar to this happened in NYC? The true sentiment should be a desire for those who commit such crimes to be punished, not to try to turn this into some BS regional dig at each other.