WARNING: GRAPHIC CONTENT
A WITNESS to the deadly Las Vegas shooting has described seeing concertgoers "plugging bullet holes with their fingers" in the massacre's bloody aftermath.
At least 58 people died and more than 515 people were injured when a 64-year-old man sprayed bullets down on the Route 91 Harvest Festival from his room on the 32nd floor of a nearby hotel and casino on Sunday night.
Russell Bleck, who was in the crowd for Jason Aldean's set when the bullets rained down, said he saw wounded people "everywhere".
"Thank God it was a country concert. You saw a lot of ex-military just jump into gear," he told NBC News.
"I saw guys plugging bullet holes with their fingers.
"While everyone else was crouching, police officers were standing up as targets, just trying to direct people to tell them where to go.
"I mean, the amount of bravery I saw there was just - words can't describe what it was like.
"There were 10-foot walls boxing everybody in; we couldn't escape."
Mr Bleck explained how the crowd initially confused the sound of gunfire with pyrotechnics on stage.
"After the first few bursts, which sounded like firecrackers or an amp crackling, Jason Aldean didn't even stop playing," he said.
"And then all of a sudden, I was shooting video of his performance and I was like, you know on second thoughts, it sounds like an AR15 and then, sure enough, it was an automatic rifle, without a doubt.
"He was just spraying the crowd. I mean, it was relentless. There was no stopping.
"We had only five, maybe eight seconds to move from cover to cover to try to move and get out of there as he reloaded."
Mr Bleck also posted a chilling video on Instagram which shows concertgoers running for their lives and huddling under a tent.
The sound of gunfire is non-stop during the video, which he posted with the caption "Scariest moment of my life".
CHILLING MOMENT THINGS CHANGED
Eyewitness video shows the moment musician Jason Aldean realises he is in danger at a music festival in Las Vegas, in what turned out to be the deadliest shooting in US history.
Footage filmed by fan Hannah Dorfman shows Aldean singing while the sound of automatic gunfire can be heard.
The band continues to play, before the sound stops and they realise what is going on. Aldean runs off stage for cover.
The same moment has been captured from multiple angles on eyewitness video, showing a dawning realisation the sound is not pyrotechnics or part of the show.
In one video people can be heard yelling "get down" and "don't push", while many described covering their loved ones to protect them.
Later, more frantic scenes appeared on social media with reports of people delivering first aid in the open and running to hide anywhere they can.
EYEWITNESS: Chilling footage of moment active shooter opened fire on concert goers near Mandalay Bay resort in Las Vegas pic.twitter.com/7OfAwg0ReO— Josh Caplan (@joshdcaplan) October 2, 2017
'I THOUGHT THIS IS IT'
Eyewitnesses including an Australian family and a professional poker player have spoken about how they feared for their lives during the deadly massacre.
Brenton Wingard said he had been to the same concert four years in a row when he heard what he thought was firecrackers.
"Everyone started looking around and up in the sky thinking it was firecrackers. Then we heard it again, tap-tap-tap," he said. "I thought it was coming from somewhere near the toilets."
"The third time we heard it I saw someone on the ground being given CPR. I thought to myself what the hell is going on?"
The brother of South Australian Sport and Racing Shadow Minister Corey Wingard said he hid under some bleachers with his wife and friends after ripping off the cladding to crawl inside.
"We crawled under there and waited five minutes, which seemed like forever when we heard thuds from above us,"
Brenton said. "I thought this is it, this is the end, but it was just someone who told us I get out and run."
"I asked him whether it was safe and he said 'I don't know, but the shooting has stopped and know is the best time to go'.
"So we crawled out and took off across the field where people had been shot.
"Bodies were lying there and others were being hauled off in make shift stretchers.
"We didn't see any police until we got to the back of the stage where there were two officers ducking behind a car ...
They just said keep running."
POKER PLAYER CAUGHT IN CHAOS
Professional poker star Dan Bilzerian was watching the concert from the side of the stage and posted a story on his Instagram account saying it was "f***ing crazy."
"Holy f**k this girl just got shot in the f**king head," Bilzerian said.
"So f**king crazy … So I had to go grab a gun, I'm f**king heading back … Some kind of mass shooting … Guy had a heavy caliber weapon for sure."
"Saw a girl f**king get shot in the face right next to me, her brains f**king hanging out," he said.
WARNING GRAPHIC LANGUAGE
NSW family, Kevin Comerford, Nicole Shipman and her daughter Maddy Aspinall, 14, told of the "scariest night of our life" after they were forced to walk with their hands up across the empty casino.
Mr Comerford told AAP they rode in a helicopter over the Grand Canyon and returned to their hotel two blocks from the shooting.
"This was supposed to be a one night special stop because we'd never been to Las Vegas before ... we were planning to live it up for one night and we've had probably the scariest night of our life," he said, adding that their teenage daughter coped well with the horror.
"That is until we got to the hotel and the police had us walk through the empty casino with our hands above our head and it became very, very real for her then," he said. "That's when she got very upset. She's been a brave girl."
'THEY WERE UNLOADING CLIP AFTER CLIP'
Eyewitness reports on social media showed people recalling hearing bursts of gunfire from a high vantage point and not being able to tell where it was coming from.
A young man and woman who were at the Jason Aldean performance saying there were "bullets flying everywhere".
"Everybody was running it was really, really, really bad," the young man said.
"They were ricocheting everywhere. They were firing from somewhere high and they were unloading clip after clip after clip.
"It was hundreds of shots ... people are still running scared."
Another witness told CNN people were "laying on top of each other trying to get out of the way and the shots just kept coming."
"Everybody was hiding everywhere," she said, adding that she ran out to her car with her husband to get away. "There was a gentleman that was shot and he said 'could you help me?' And so I put him in my car and I had like six people in my car."
More than 50 people died and more than 200 were injured after the shooting that occurred during the performance at the Route 91 Harvest country music festival Sunday night.
Musician Jason Aldean said he was "heartbroken" about the event in a post on Instagram.
"Tonight has been beyond horrific," he wrote. "I still don't know what to say but wanted to let everyone know that Me and my Crew are safe" (sic).
"My Thoughts and prayers go out to everyone involved tonight. It hurts my heart that this would happen to anyone who was just coming out to enjoy what should have been a fun night."
'ENDED UP DYING IN MY ARMS'
One witness told ABC news he had just found out his friend would be OK after being hit three times by the shooter during the deadly chaos. The unidentified witness said he was with two others who were also injured and they ran under the stage to hide and wait for help.
"One guy ended up dying in my arms," he said. "We got three more people in the ambulance."
Another witness known as Jake told ABC News he had a "birds eye view" of the music festival from the 64th floor of a nearby hotel where he was drinking in a bar.
"We saw bodies hitting the ground. We actually watched these people getting gunned down," he said.
"When the elevator got the to lobby, the air just reeked of gunpowder."
Canadian Quinn Mell-Cobb was in the venue with his girlfriend when he said the shooting began.
"I saw my girlfriend go down so I was worried she might have been hit," he said.
"It sounded like it was coming from everywhere ... It's one of those situations you never think you're going to be in."
Video from the scene shows crowds outside in the open air festival scattering and ducking for cover as gunfire is heard. Others run for their lives or try to shield their loved ones.
Thirty-six-year-old Kodiak Yazzi said the music stopped temporarily and started up again before another round of pops sent the performers ducking for cover and fleeing the stage.
As the 40,000 fans in the crowd began to flee, Yazzi took cover and said he saw flashes of light coming from the Mandalay Bay hotel tower high above.
The bursts of pops would start and stop for more than five minutes. He says he saw dozens of ambulances as he ran for safety. He later got a Lyft driver to take him home to suburban Henderson.
Authorities shut down part of the Las Vegas Strip and Interstate 15. Some flights destined for the McCarran International Airport were diverted due to incident.
Australia's Consulate General in LA is making urgent inquiries with local authorities to determine if any Australians have been injured or killed.
"If you have any concerns for the welfare of family and friends in the Las Vegas area, you should attempt to contact them directly," a Department of Foreign Affairs and Trade spokeswoman told AAP.
People unable to make contact with loved ones should phone the DFAT emergency hotline: 1300 555 135, or +61 2 6261 3305.
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