By Steve Large

NATOMAS (CBS13) — The barren Sleep Train Arena will suddenly be bustling Thursday.

But not in the way we’ve seen before.

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Emergency first-responders, including members of the U.S. Air Force, will be descending on the old building for a massive training exercise.

“Don’t panic, its only an exercise,” Cal OES Spokesperson Shawn Boyd said.

The dramatic storyline that includes a truck bomb and nuclear radiation is only fictional. The disaster drill is for first responders to train for real-life terror attacks.

“First responders are going to be coming in in total darkness because the power would have gone out,” Boyd said.

Boyd said Sleep Train Arena creates a perfect set of problems for emergency workers.

“It has hiding places; it has shadows, it has dark corners,” Boyd said.

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For people who live near Sleep Train Arena, the action at the arena will be more than they’ve seen in months.

“In the nine of 10 months we’ve been here, there’s been nothing,” Kevin Olmsted said. “It’s overgrown, it’s kind of scary, especially at night.”

Sacramento Kings owners promised to redevelop the Kings’ old home court when the team moved downtown.

In a statement the Kings organization wrote in part: “We continue to work with city leadership on securing entitlements.”

The Kings are not charging first responders to use the building for their training.

“The key thing here is when people see what they’re going to see, don’t panic,” Boyd said.

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A wild training day in the works at Sleep Train Arena while Sacramento wonders, what’s next for this old building.