When a crazed illegal alien attacks a man who requires a walking stick to perambulate, what happens legally?

when the injured individual bops the alien attacker with the stick, which then breaks into two pieces, so the crazed alien persists in posing a clear and present danger to the perambulator, so he jabs the pointy end of the peramblulation istance device straight through the vicious attacker's jugular, causing the uninvited criminal alien to bleed out in 5-minutes-or- so?