From the 10 Stages Of Genocide:

#4. DEHUMANIZATION: One group denies the humanity of the other group. Members of it are equated with animals, vermin, insects or diseases. Dehumanization overcomes the normal human revulsion against murder. At this stage, hate propaganda in print and on hate radios is used to vilify the victim group. The majority group is taught to regard the other group as less than human, and even alien to their society. They are indoctrinated to believe that “We are better off without them.” The powerless group can become so depersonalized that they are actually given numbers rather than names, as Jews were in the death camps. They are equated with filth, impurity, and immorality. Hate speech fills the propaganda of official radio, newspapers, and speeches.

To combat dehumanization, incitement to genocide should not be confused with protected speech. Genocidal societies lack constitutional protection for countervailing speech and should be treated differently than democracies. Local and international leaders should condemn the use of hate speech and make it culturally unacceptable. Leaders who incite genocide should be banned from international travel and have their foreign finances frozen. Hate radio stations should be jammed or shut down, and hate propaganda banned. Hate crimes and atrocities should be promptly punished.