Floors two to five and several corridors of the Pentagon were locked down on June 11, with many people also evacuated from some areas, CNN reported, citing sources.
Arlington County Fire and Rescue, the jurisdiction where the US Department of Defense headquarters is located, announced they were investigating an incident involving hazardous materials. According to CNN, emergency responders wore respirators and chemical protective suits to manage the situation.
![]() |
An aerial view of the Pentagon on 31/5. Photo: AFP |
An aerial view of the Pentagon on 31/5. Photo: AFP
"The Pentagon has sophisticated systems to ensure the safety of the building and its occupants. These systems detected an air quality issue, necessitating precautionary measures until we determine the severity," said Pentagon spokesperson Sean Parnell. He added that the US Department of Defense was implementing standard protective procedures, including a shelter-in-place order for affected areas. Response teams were on site and ready to assist those inside the building.
The hazardous materials response team from the Pentagon Force Protection Agency is handling the incident with support from the Arlington County fire department. The Pentagon's security division stated that additional testing was required.
![]() |
Location of the White House and the Pentagon. Graphic: Mapbox |
Location of the White House and the Pentagon. Graphic: Mapbox
"Additional testing could take one to two hours. People may see responders from multiple agencies and precautionary measures being applied in the central courtyard area. Please do not overinterpret this activity," read an announcement from the security division.
The Pentagon is one of the world's largest office buildings. The facility was attacked during the 11/9/2001 terrorist incident.
Huyen Le (According to Reuters, CNN)

