Joint Base Elmendorf-Richardson is hosting an exercise Thursday morning in preparation for a major air show this summer, asking people to avoid a small area of the base for much of the day.

A post on JBER’s Facebook page described the incident as a “mission assurance exercise,” asking people to avoid the area around the base headquarters building near Davis Highway and Vandenberg Avenue.

According to a KTVA viewer, loudspeakers on base Thursday morning were broadcasting orders for personnel to get down on the ground.

Air Force 2nd Lt. Brigitte Brantley said the activity was linked to the base’s biennial Arctic Thunder open house, slated for the weekend of June 30 and July 1.

Thursday’s exercise, Brantley said, was “a chance for first responders, medics and others to see how they would respond in an emergency scenario.” She declined to say what that scenario was, citing security reasons.

Base residents and service members received advance notice of the exercise, which has been planned for months, with additional notices sent out Thursday. The exercise started at 8 a.m., and may continue as late as 4 p.m.

“The main determination for that is if all objectives have been achieved,” Brantley said.

No other areas of the base should be affected beyond the vicinity of the headquarters building.

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