(a) The Secretary, either pursuant to a complaint or otherwise, shall, as may be appropriate, investigate and, in connection therewith, enter and inspect such places (including housing and vehicles) and such records (and make transcriptions thereof), question such persons and gather such information as he deems necessary to determine compliance with the Act, or these regulations.

(b) The Secretary may issue subpenas requiring the attendance and testimony of witnesses or the production of any evidence in connection with such investigations. The Secretary may administer oaths, examine witnesses, and receive evidence. For the purpose of any hearing or investigation provided for in the Act, the Authority contained in sections 9 and 10 of the Federal Trade Commission Act (15 U.S.C. 49, 50), relating to the attendance of witnesses and the production of books, papers, and documents, shall be available to the Secretary. The Secretary shall conduct investigations in a manner which protects the confidentiality of any complainant or other party who provides information to the Secretary in good faith.

(c) Any person may report a violation of the Act or these regulations to the Secretary by advising any local office of the Employment Service of the various States, or any office of the Wage and Hour Division, U.S. Department of Labor, or any other authorized representative of the Administrator. The office or person receiving such a report shall refer it to the appropriate office of the Wage and Hour Division, for the region or area in which the reported violation is alleged to have occurred.

(d) In case of disobedience to a subpena, the Secretary may invoke the aid of a United States District Court which is authorized to issue an order requiring the person to obey such subpena.