There shall be established within the administrative staff a unit to investigate all matters pertaining to the fraudulent acquisition of public aid, including administrative funds. The investigation may be conducted without prior notice to the recipients, to the personnel administering the cases or to vendors or other persons involved. The unit shall also investigate any other matter relating to the administration of public aid assigned to it by the Director of the Illinois Department. The Illinois Department may make the facts revealed by any investigation available to the Attorney General or to the appropriate State‘s Attorney.