Final answer:
The next step after securing classified material is to report the incident promptly to the designated security authorities within the organization or government entity for breach evaluation and damage control.
Step-by-step explanation:
After properly securing the classified material, the next step in reporting an Unauthorized Disclosure involves immediately reporting the incident to the appropriate security authorities within your organization or government entity. This may include your immediate supervisor, security officer, or a designated contact within the security office. Timely reporting is crucial as it enables the authorities to evaluate the breach, assess the potential damage, and initiate measures to prevent any further compromise of sensitive information. Depending on the specific protocols of the entity, the incident may also have to be reported to higher-level government agencies tasked with overseeing national security and classified information.