Upon the application of the collector of revenue or any railroad company, shipping transportation company, or armored car company transporting money or other valuables within this state for the appointment of police officers, the department may appoint persons whom it thinks qualified and competent for purposes of protection.  The department may also appoint any other officers, agents, and employees necessary for the rendition of efficient service.  Every person so appointed shall have the rank and title of special agent and shall be governed by this Sub-part when so designated by the department.  

The department may revoke the commission and authority of any person appointed under this Section.