Federal, state, and local officials, along with medical professionals, participated in a large-scale homeland security exercise called Operation Harbor Shield in Middle River, Maryland. The event took place on September 30, 2025, and involved approximately 375 participants from various agencies.
The exercise was designed to test interagency coordination and incident response plans by simulating two mass casualty events: an active shooter situation in a seaport building and a scenario involving both an active shooter and a drone-deployed improvised explosive device at a concert venue. Organizers aimed to identify gaps in capabilities, communications, interoperability, and equipment among the participating agencies.
U.S. Customs and Border Protection (CBP), the University of Maryland Medical Center, and the U.S. Air Force Center for the Sustainment of Trauma and Readiness Skills (C-STARS), Baltimore planned and coordinated the exercise. Other agencies involved included the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), Maryland State Police, Maryland Transportation Authority Police, Baltimore County Police, Baltimore County Fire Department, and Baltimore City Police Department.
Medical staff from the R Adams Cowley Shock Trauma Center at the University of Maryland Medical Center received simulated patients transported by ground vehicles and helicopters to its Trauma Resuscitation Unit. First responders were also provided training on lifesaving care during the event.
About 125 volunteers acted as victims with varying degrees of injury to create realistic conditions for first responders to practice decision-making under stress. Between scenarios, participants engaged in tactical and trauma training covering incident command procedures, weapons handling skills, room clearing techniques, triage methods, tourniquet application, wound packing practices, and airway management.
“Mass casualty incidents are horrific, and we hope we never have to experience one, but how well we are collectively prepared to respond to a mass casualty event could make a difference in how many lives we save,” said Jason Kropiewnicki, CBP’s Acting Area Port Director in Baltimore. “Response plans are just words unless they are challenged and improved through multi-agency and multi-discipline exercises such as Operation Harbor Shield.”
“We are grateful to have been a part of such a well-coordinated training exercise,” said Tony Christiani, Simulation Program Administrator of the C-STARS Sim Lab Center in Baltimore. “As Maryland’s only Primary Adult Resource Center level trauma center and the heart of the state’s EMS trauma system, our Shock Trauma and C-STARS clinical teams are dedicated to being in a constant state of readiness to save lives in the aftermath of a large-scale mass causality event. While this is an experience we all hope to never live, it is critical to partner with federal, state and local agencies across the region to ensure we are ready to work together seamlessly to answer the call when comes.”
The U.S. Army’s Combat Capabilities Development Command Army Research Laboratory hosted Operation Harbor Shield at its Gracie’s Quarters training site.
Operation Harbor Shield followed guidelines from the Department of Homeland Security’s Homeland Security Exercise and Evaluation Program. Such exercises allow communities nationwide to assess planning efforts while validating their ability to respond effectively during emergencies.
CBP is recognized as America's largest law enforcement organization responsible for border management on land, airspace boundaries or sea routes—supporting national security by enforcing travel regulations as well as facilitating lawful trade.
Photos from Operation Harbor Shield can be found at https://flic.kr/s/aHBqjCvYsm.
