I'm saying reasonable threat, my man.
Even if they killed the neighbours there's no way to know that, IMO it's not worth risking my own life (leaving my family without a father/husband) to apprehend a criminal that has already ended the life of my neighbour. Maybe if you heard gunshots, it might be justified, because you'd know shit went down.... but if not, why would you assume there's been a murder or assault?Killing the criminal isn't going to bring my friend (neighbour) back, even if you assume the worst case scenario, and getting myself killed is counter-productive too. If I saw them headed my way, I'd cap their asses, but lets be honest that's not likely...
Even if you're Joe Horn.