Quran says, “Co-operate with one another for virtue and seedfulness and do not co-operate with one another for the purpose of vice and aggression.” This means that a person who does noble and righteous deeds has the right and active cooperation.
On the controrary, see who commits acts of vice and aggression. Even if the aggressor is a close relation, friend or neighbour, he does not have the right to win our support in the name of religion, race, country, language or nationality.
The Prophet said, “You render help to your brother, whether he be an aggressor or victim of aggression.” The companions of the prophet asked him how they can help an aggressor. The Prophet replied, “By preventing him from his act of aggression.” On another occasion the Prophet said, “The ugliest face of a communal bias is to help the aggressor who belongs to ones community in his act of aggression.”