"If anyone is killed and his killer is not known, or was killed with a stone, a whip or with a stick (i.e. killed by mistake but with a deliberate injury) his Diyah will be that of killing by mistake (manslaughter). As for whoever killed deliberately, retaliation is due (from the one who killed him). Anyone who tries to prevent taking Qisas (from the killer) may Allah curse him." Related by Abu Dawud, An-Nasa'i and Ibn Majah with a strong chain of narrators.