BOISE -- The outdoor music festival turned surreal horror show on the Las Vegas Strip has many Americans feeling on edge about concerts or events. A barrage of bullets suddenly came raining down into the crowd of about 22,000 people as they were dancing and singing along to country star Jason Aldean.

The lingering, disturbing thought on many of our minds: From a security standpoint, could this have been prevented at all?

Many locals are wondering what security measures are taken to protect them at events that take place here. KTVB spoke with local law enforcement and concert venue managers about how they prepare for the worst.

In the wake of the largest mass shooting in modern American history, officials and venue managers from Nevada to Idaho on Monday said there's a heightened level of awareness.

"Certainly something any venue has to pay attention to," CEO of CMoore Live, which produces the Outlaw Field Summer Concert Series at the Idaho Botanical Gardens, Chris Moore, said. "From our company's standpoint, we've always been very proactive with our concertgoers' safety. That's our number one concern at any event we do."

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Local law enforcement such as the Boise Police Department play a huge role in everything from races to concerts, and BPD has an entire unit dedicated to training officers for those special events.

"Providing them knowledge and the ability to respond to those type of events, pre-plan for those type of events, look at crowd control. All of those type of elements that are necessary for a crowd or concert event or venue," Lt. Greg Oster, with the Boise PD training unit, told KTVB. "We kind of follow a matrix."

They say they plan according to many factors, such as crowd size, anticipated characteristics of the crowd, who is performing, and the nature of the venue.

"Whether it be an indoor or outdoor event, our officers are monitoring the threat areas. Prior to most of our events, officers go out and actually do a threat assessment - looking at potential threats, where a person could be, where they might be," Lt. Oster said.

Oster says outdoor events are more conducive to evacuations of larger crowds than indoor venues.

"You have exits, people coming out a very small funnel, we're having officers and first responders trying to work their way back through those and it just makes it very difficult," Oster added. "Versus an outdoor arena: you're typically going to have places you can run for cover. You can run, hide, and get away from the event."

Depending on the event and venue, police may also be working alongside security hired for each event to set up a mutual aid plan. Typically, those security companies or in-house security know the venue very well and are good at reading the crowd, BPD says.

"The hard part though, for example, in the Vegas incident where you have a shooter that's elevated and you have a ton of people down who are victims. And there's no place for them really to go at that point," Lt. Oster added.

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A law enforcement expert told NBC News on Monday that the mass shooting was especially deadly because of how the shooter was positioned: unobstructed, protected and high above the crowd he was targeting at the Route 91 Harvest festival at the Las Vegas Village - effectively a sniper's perch.

"It makes it very difficult in those type of situations," Oster added. "You can't plan for everything. So you kind of take, again, what is our matrix."

It's especially difficult - nearly impossible - to plan for an unforeseen threat like this.

"This is not like an 'oh, how do we react to this?' We've always been proactive. And you cannot control everything that is thrown at us," Moore added.

"No agency in the United States has enough bodies to cover every potential threat," Lt. Oster added. "We could have something similar to that any time, any place in this country. And we've seen similar events all over the country and the world. So you kind of think about what's the worst case scenario - you try to come up with a plan for that. We prepare for the worst and we pray for the best."

In outdoor venues such as the Idaho Botanical Garden and Ford Idaho Center Amphitheater, along with security posted throughout there are also metal detectors, bag searches, fences or barricades. There are now K-9 units at the Idaho Botanical Garden concerts to detect any explosive devices.

In light of this horrific event, law enforcement is encouraging people to pay attention to their surroundings: if you see something that doesn't look right, say something.

"Have what some people call situational awareness. But really pay attention to your surroundings. If you see something unusual, point it out. And use your instincts," Oster added.