The Pentagon was placed on lockdown Tuesday as authorities investigated a report of a hazardous material within the building. The lockdown affected the Pentagon Reservation, including the Pentagon itself, prompting a response from emergency services. Initial reports indicated the presence of an unidentified hazardous substance, triggering precautionary measures. The situation was later resolved, and the lockdown was lifted after a thorough investigation by hazmat teams. Officials have not yet disclosed the nature of the material or the cause of the incident, but stated there is no immediate threat to personnel. The investigation remains ongoing to determine the source and details surrounding the hazardous material.