June 11, 2026

File: An aerial view of the Pentagon, which houses the US Department of Defense headquarters, in Arlington, Virginia, on May 31, 2026. Photo by Daniel SLIM / AFP.

Part of the Pentagon went into lockdown on Thursday, a spokesman said, in response to what a local fire department described as a “hazardous materials incident” at the US military headquarters.

The Arlington County Fire Department said in a post on X that it had units “including our Hazardous Materials Team” operating at the Pentagon during what it described as a “hazardous materials incident.”

The fire department did not provide further details on the nature of the incident.