LAS VEGAS -- At least one Idahoan was shot in the chaos that erupted when a lone gunman fired hundred of rounds down into a packed crowd at an outdoor Las Vegas music festival Sunday night.

Jason Hammond of Emmett was shot in the knee during the onslaught, and is awaiting surgery, friends confirmed Monday.

Hammond is one of more than 500 people wounded in the attack, which killed at least 58, police say. The violence marks the deadliest mass shooting in modern American history.

The gunman, identified as 64-year-old Stephen Paddock of Mesquite, Nevada, fired into the crowd from his hotel room on the 32nd floor of the Mandalay Bay Resort and Casino. He killed himself as a SWAT team closed in on his room, police say.

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Meridian resident Scott Freund, who was attending the Route 91 Harvest country music festival for the second time, said at first, he and the other concert-goers did not realize what was happening.

The first round of gunfire came at about 10:10 p.m. local time during Jason Aldean's set, and sounded like "quiet fireworks," he said.

Freund said several people began to look around, but the music kept playing. Then Paddock began firing again.

"And then this guy opened up the big guns, and I don't know what caliber these guns are, what he was using, but they were extremely loud," he said. "It was so loud, it drowned out the music, and then they finally figured out that people were getting shot."

Aldean stopped playing, and ran from the stage, he said. In the crowd, pandemonium struck.

"It was just complete chaos everywhere. Everybody is running every direction, nobody knew where it was coming from," Freund said. "It sounded like it was coming from above somewhere. People were looking up, but you just grabbed whoever you were with, and ran. Everybody just ran for their lives."

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Jason Barinsky of Meridian, who was at the concert with his wife and friends, said he saw people trying to hide behind tables and make themselves small on the ground. The gunfire seemed to stretch on indefinitely, he said.

"My wife kept saying, 'when's it going to stop, when's it going to stop?' because it just kept going," he said.

Barinsky said he and his group ran through a vendor area to try to escape, but were blocked in by a high chain link fence.

"There was some stuff stacked against it, and I was able to get on that, get my wife over, I got over, and we were able to make it to our hotel," he said.

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Freund said the mayhem was compounded when people fleeing the festival ran into casinos and hotels to take shelter.

"Everybody's running in there saying there's a shooter, so then there was confusion - everybody thinks there's a shooter in MGM, so then everybody is running out of that casino," he said. "There were reports that there were five or six shooters in all these casinos, and it was just complete chaos."

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He said hotel guests were letting strangers into their rooms and casino employees were hiding people in kitchens and back rooms as police flooded the scene. Freund did not make it back to his own hotel room in Mandelay Bay until morning.

Speaking to KTVB by phone from that room Monday, Freund said he still had a front-row seat to the carnage of the previous night.

"On the left of me are the two windows this guy just broke out and shot from. I'm looking down at the venue right now, and they are still removing deceased people from the venue," he said. "It's horrific. It's absolutely horrific."

Freund said he was hoping to fly back to the Treasure Valley as soon as he could Monday. As the reality of the dozens dead and scores wounded continues to sink in, Freund said he took solace in the bravery and compassion on display Sunday night, even as bullets were raining down on the crowd.

"I can tell you that it was amazing how people were helping people - even though it was complete chaos and panic, people were still helping anyone they could," he said. "People stayed and helped people that were shot, and helped haul people to hospitals."

Diana Murkle of Meridian also attended the Route 91 Harvest festival, and says a last-minute decision to upgrade her ticket may have saved her life.

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Murkle said she and a friend had attended the first two days of the festival standing in the thick of the packed-in crowd. On Sunday, the pair decided to pay extra for a little more breathing room in a different section - deck seating on the opposite side of the venue from Mandelay Bay

"I looked at my friend and I just said, do you want to upgrade and sit up here?' because we'd just had two nights of guys in cowboy boots stepping on our toes," she said. "I think somebody was looking out for us for sure."

After the shooting began, the crowd turned "panic-stricken," she said. No one seemed to know where the bullets were coming from, or what was happening.

"We really thought there were multiple shooters, and possibly something like maybe a terrorist attack," she said.

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Murkle said she saw people who were injured and people covered in blood as she ran from the festival. Both she and her friend made it back to the hotel safely.

Clark County Sheriff Joe Lombardo said the death toll could continue to rise. Police recovered at least ten guns from Paddock's hotel room, and are working now to search his home in Mesquite.

A motive in the shooting is unknown, leaving Murkle and others across Las Vegas with more questions than answers.

"Why did this guy do this?" she asked. "He specifically got a room to overlook this venue, and just take target practice at people there to have a good time. It just makes no sense."