U.S. media reported a suspected hazardous materials incident at the Pentagon. CNN reported that a lockdown was imposed on several floors of the sprawling building, while employees in other locations were instructed to evacuate. A source familiar with the details told the news network that officers donned gas masks and wore chemical protective gear. Pentagon spokesperson Sean Parnell said the building's systems detected 'an air quality issue that required protective measures until we could determine its significance.' The spokesperson added that in accordance with 'standard procedures,' employees were instructed to shelter in place in areas affected by the detected issue.

