A simulated blast and a few moments of chaos kicked off a realistic antiterrorism exercise (ATEX), here, Aug. 20.

The 9th Mission Support Command's U.S. Army Reserve Theater Support Group-Pacific was the executive agent for the one-day, multi-agency exercise.

Oahu-based participating units and multi-agency partners included the 9th MSC, USAR TSG-Pacific, the 303rd Maneuver Enhancement Brigade, the 1984th U.S. Army Hospital (USAH), the 706th Ordnance Company (Explosive Ordnance Disposal), the Federal Fire Department and the Honolulu Police Department.

The participants began with a "blast" around 9:30 a.m. After the simulated explosion, the coordination began.

Less than 10 minutes after the explosion, the fire department and the EOD team arrived on the scene. EOD quickly removed two "casualties" to a secure staging area.

The fire department then assessed the patients, conducted triage and on-scene treatment, and evacuated each casualty by ambulance. EOD went in to check the area for additional explosive devices, following its tactics, techniques and procedures, once the simulated victims were removed.

The event coincided with antiterrorism awareness month and was the culmination of approximately 10 months of planning. In addition to the Oahu event, USAR TSG-Pacific also held exercises on Maui, the Big Island, Alaska, Guam, Saipan and American Samoa.

In American Samoa, USAR TSG-Pacific personnel partnered with Veterans Affairs, the territory's Homeland Security Department and local law enforcement.

The USAR TSG-Pacific provides base support and services to Pacific Army Reserve Soldiers throughout the 9th MSC's area of responsibility. This exercise was its first full-scale exercise.

TSG-Pacific conducted a tabletop exercise in November 2011 and participated in another tabletop with U.S. Army Garrison-Hawaii in July 2013.

ATEXs are one way to validate that an organization has the correct resources and trained personnel to defend against terrorist incidents.

Col. Eddie Rosado, commander, USAR TSG-Pacific was at the Oahu event to observe.

"(The exercise) gives us an opportunity to practice our antiterrorism plans," Rosado said. "The ATEX is a collective, proactive effort focused on the prevention and detection of terrorist acts."

To make the exercise more realistic, the 1984th USAH moulaged role players with realistic-looking injuries that included broken bones and the appearance of severe bleeding.

At the end of the exercise, Rosado was pleased with the outcome.

"The exercise has been a valuable event for all organizations involved," said Rosado. "Next year, we are looking to add more agencies (to the ATEX) and use more simulation and technology."