Whenever it shall appear to the Director that any person is engaged or about to engage in any acts or practices which constitute or will constitute a violation of the provisions of this chapter, or of any rule or regulation prescribed pursuant thereto, he may, in his discretion, bring an action in any district court of the United States, or the United States District Court for the District of Columbia to enjoin such acts or practices, and, upon a proper showing, a permanent or temporary injunction or restraining order shall be granted without bond. The Director may transmit such evidence as may be available concerning such acts or practices to the Attorney General who may, in his discretion, institute the appropriate criminal proceedings under this chapter.