The Garda Síochána is responsible for investigating complaints of illegal employment of migrant workers and the details supplied have been referred to the Garda National Immigration Bureau for investigation. Migrant workers could be permitted to work without work permits in any of the following circumstances: persons who are EEA citizens — the EEA consists of the EU together with Norway, Iceland and Liechtenstein; Swiss nationals, in accordance with the terms of the European Communities and Swiss Confederation Act 2001, which came into operation on 1 June 2002, and enables the free movement of workers between Switzerland and Ireland, without the need for work permits; persons who have been granted refugee status; non-EEA nationals who have permission to remain in the State as students are entitled by the Department of Justice, Equality and Law Reform to take up casual employment, defined as up to 20 hours part-time work per week, or full-time work during vacation periods, for the duration of their permission to remain; and persons who have been granted permission to remain in the State on one of the following grounds: persons with permission to remain as spouse of an Irish national, persons with permission to remain as a parent of an Irish national, and persons with permission to remain on humanitarian grounds having been in the asylum process.