Update: Pentagon spokesperson Sean Parnell gave the all clear and said “Earlier this morning, Pentagon occupants were notified of a potential air quality issue, prompting immediate precautionary safety measures and evaluation. Subsequent testing confirmed no hazard exists, and normal operations have resumed.”

“We express our sincere appreciation to the first responders for their swift actions to ensure the safety of all personnel,” he added.
Original Story: The Pentagon went on lockdown on Thursday while some floors were evacuated. CNN's Haley Britzky reported on the issue and said on X “Multiple floors and corridors inside the Pentagon have been locked down and others are being evacuated, three sources familiar with the situation told CNN.”
Why Pentagon went on lockdown?
Arlington Fire & EMS confirmed the incident at the US military headquarters. They noted that there was an incident linked to hazardous materials.
“ACFD units, including our Hazardous Materials Team, are currently operating at the Pentagon in support of PFPA’s Hazmat Team during a hazardous materials incident,” the statement read. “PFPA is primary on this incident. Please go direct to them for any further information,” they further said.
However, the Pentagon Force Protection Agency is yet to issue a statement on the incident.
Meanwhile, Pentagon spokesperson Sean Parnell confirmed that systems within the Pentagon had detected “an air quality issue necessitating precautionary measures until we determine its significance.”
“The Pentagon has sophisticated systems to ensure the safety of the building and its occupants. Those systems have detected an air quality issue necessitating precautionary measures until we determine its significance. The Department is executing standard protection protocols, including a shelter-in-place order for the affected area. Response teams are in place and ready to support building occupants,” he said on X.
The Pentagon is the headquarters of the United States Department of Defense.
“Response teams are in place and ready to support building occupants,” the spokesperson further said.
A message was also sent from the Pentagon security team which said there was an ‘air quality issue’ and it needed additional testing, CNN reported.
“This additional testing could take one to two hours. Response teams are in place and ready to support building occupants if necessary. You may observe response personnel from multiple agencies and precautionary measures taking place in the center courtyard. Please do not interpret these activities,” the message read.
The publication noted floors two through five in corridors four through seven had been locked down, as per their sources. Police were reportedly seen wearing gas masks and full chemical protective gear.
Pentagon incident comes as Trump vows to strike Iran
The incident at the Pentagon was reported on the same day that President Donald Trump vowed to strike Iran ‘very hard’. In a Truth Social post Trump announced that the US would hit Iran tonight and even outlined plans of taking over Kharg Island sometime in the future.
Trump said the situation would be something akin to Venezuela, where troops had gone at the direction of POTUS and captured their president and his wife, who were flown to the US to face indictment.