At first, the popping sound seemed like a prank.
Country music artist Jason Aldean continued to play on a clear, Las Vegas Sunday night before more than 20,000 fans, with the golden glow of the Mandalay Bay hotel framed in the background.
Dan Conti, a Greenville businessman who flew out to Las Vegas with a friend to the three-day Route 91 Harvest Festival, was yards away from the stage when the sounds of gunshots became more guttural.
"He was in the middle of a song, and we heard 'pop-pop-pop,'” Conti told The Greenville News by phone Monday as he waited to catch a flight back home. "I looked at my buddy and said, 'firecrackers?' There was a pause, and he kept playing. Then 'pup-pup-pup-pup-pup-pup.'"
The singer left the stage. The lights went black. Then there was another pause.
“I said, ‘Let’s get the hell out of here.’ Everybody else was still on the ground,” Conti said. “We just started sprinting."
He had seen some blood and injuries, but it wasn’t until the wee hours of Monday morning that he learned the scale of violence – at least 58 dead, more than 500 wounded in the largest mass shooting in modern American history.
And it wasn't until the morning that he knew the shots had come from the hotel, where authorities say 64-year-old Stephen Paddock fired automatic weapons from a 32nd-floor room.
The Upstate joined the country Monday in trying to make sense of the massacre and checking on those they know who lived in or were visiting Las Vegas.
Diane Moore was worried about her stepdaughter, Ashley Moore, who had talked about attending the music festival. She rushed to check Facebook and discovered Ashley had been in the center of the gunfire.
"Bless her heart. It was so scary," Diane said. "Some guy she didn't know laid across her and her friend."
Ashley described in a Facebook post how she saw a man die but was helped by a man who covered her and a friend during the shooting. They found safety under the stage.
"I couldn’t be more thankful for him trying to keep us safe,” Ashley wrote. “The whole time laying there, I was just waiting to be the next one with a bullet to my back and that was all I could think about."
Rob Wansley, an Anderson native who moved to Las Vegas six years ago to further his career as a musician, intentionally avoided the Strip late Sunday night.
Wansley knew it was final night of a three-day homage to country music, and he didn't want to get caught up in the festival crowd.
“I had no idea it was anything of this degree,” he said. “But then my Facebook starting lighting up with people from home wanting to know if I was OK.”
Wansley said he is planning a trip back to Anderson soon so he can reconnect with family and friends in person.
"You expect things to happen in a big city that don't happen at home in Anderson," he said. "But I never expected something like this. Whoever is responsible for this has messed some things up in a city that people love. It will take a while for things to recover."
In a Twitter post, Olympian Sandi Morris, a Greenville High graduate who won a silver medal in pole vaulting two summers ago in Rio, described how she was at a Blue Man Group show across the street.
After the building was locked down for five hours, Morris wrote that she "then walked to my hotel through a ghost town Vegas. Heart goes out to all victims."
Lee Brice, a Sumter native and former Clemson University football player, performed Friday at the Route 91 festival and heard about the shooting while on a tour bus in Los Angeles.
When he heard about the mass shooting he sent a text message to Jake Owen, a friend and singer who was on stage when gunfire started.
Owen sent back messages that described a scary scene: people being shot backstage as well as in the crowd, Brice said.
Brice said country music fans won't be scared from future shows.
"They're good people who want to have a good time, they work hard and are not going to let hate win," he said. "It's gonna be alright, God has a plan."
In Greenville on Oct. 21, Jason Aldean is scheduled to play a concert at the Bon Secours Wellness Arena as part of the They Don't Know Tour. Arena General Manager Beth Paul said there was no indication that the show wouldn't go on as planned.
Aldean was the closing act on Sunday.
Conti and his friend had been in Vegas for the whole festival.
The shooting began just a few songs into the set, said Conti, who owns a business in the insurance industry in Greenville.
The two heard the sound of "hundreds of rounds" of gunshots fading as they ran, but Conti said they didn't know for sure if they might be sprinting right into another shooter.
"There could have been multiple people," he said. "We could have been running right into somebody. We didn't know. It took a while before anything hit CNN or USA TODAY or whatever. I texted my family while they were asleep that I was OK."
After running to a main road, Conti said he and his friend hid behind a police car. That's when they saw a man who had been shot in the leg and was bleeding. After running across a six-lane highway, he said they saw another man bleeding who appeared to have suffered a gunshot that grazed his buttocks.
While stranded until about 5 a.m., Conti said he spoke with a couple from San Diego, who described being trampled as they tried to take cover under the stage.
"The guy said, 'I feel bad about this, but there were probably three or four people on top of me that saved my life,'" he said.
The randomness of the shooting makes Conti realize he was lucky: He happened to be on the other side of the stage from where more people were shot.
"He could have sneezed, and I'd be dead right now."