In the Buddhist monastic training rules it states "Intentionally bringing about the death of a human being, even if it is still an embryo—whether by killing the person, arranging for an assassin to kill the person, inciting the person to die, or describing the advantages of death—is a pārājika offense."
A pārājika is the worst offense in the training rules of a Buddhist monk. One immediately ceases to be a monk the moment a pārājika is committed and can never again ordain as a monk (in this lifetime at least)