The suppression of liberty of belief and action, (or the punishment of those who adhere to a particular way of life or doctrine), whether due to religions, racial or national prejudices, may include attacks upon both individuals and groups, and may be executed by single tormentors, by organized gangs, or by governments.
Although discrimination is not usually persecution, in certain circumstances, especially when there is an accumulation of acts over time, or when there is an escalation in their intensity, it may then constitute persecution or lead to a well-founded fear of persecution.
To qualify as a refugee, a person must demonstrate a well-founded fear of persecution on account of race, religion, nationality, membership of a particular social group, or political opinion. Religions persecutions, for example, have been a part of history (e.g. the Diaspora of the Jews). Modern day immigration quotas which disfavour certain groups may be considered contemporary persecution.