Overview

• The incident began shortly after 11 a.m. when an unidentified man entered the courthouse lobby with a knife, triggering an immediate lockdown and evacuation.
• Negotiators from the FBI and Department of Homeland Security, alongside Chicago police, U.S. Marshals and SWAT units, engaged the suspect for nine hours before tactical officers disarmed him just after 8 p.m.
• All occupants, including high school students visiting for a federal judiciary program, were evacuated safely by mid-afternoon with no reported injuries.
• Road closures around the Dirksen Federal Building caused major traffic delays in the Loop district during the prolonged response.
• The U.S. Marshals Service has assumed lead of an active investigation into the security breach and the circumstances surrounding the standoff.