Tweets & Videos From The Route 91 Harvest Festival Shooting Show The Unthinkable Horror Unfolding

When more than 50 people were killed Sunday night at a country music festival in Las Vegas, concert-goers already had their smartphones out to capture Jason Aldean up on the stage. Instead of one of the top country acts of the year, they captured automatic gunfire ricocheting off the stage, victims being loaded into ambulances, and hundreds crouching and ducking in fear. Tweets and videos from the Las Vegas shooting show the mayhem as it played out for nearly 10 continuous minutes, and then coming again in shorter bursts.

The gunfire began just after 10 p.m. local time and the first clue of where the gunshots were coming from were flashes of light from the Mandalay Bay Casino, across the street from the concert venue. Police found the shooter on the 32nd floor of the building, and he is now confirmed dead. Whether he shot himself or police shot him is still being investigated, Las Vegas undersheriff Kevin McMahill explained to CNN.

The most shocking, and at times even disturbing, of the tweets and videos show festival-goers running for their lives and diving onto the ground to avoid gunfire. Performers also sent out tweets in the moment, sending what could have been final messages to their loved ones. Be warned that some of the following could be upsetting.

If you would like to help and are in the Las Vegas area, here's how you can donate blood. There are also other ways to make a difference for those not in Nevada.

1) The Concert Was In Full Swing

With the music going, it was hard to hear the shots and differentiate the sounds. At one point music paused and then restarted.

2) The Mandalay Bay In The Background

In this video you can see the proximity of the hotel to the concert, and how shooting paused and restarted.

3) Eyewitnesses Explain Their Fear & Disbelief

It was hard to believe what was happening for some in attendance.

4) People Videoed Their Initial Reactions

This video and others posted to Snapchat show the fear of people hiding from the shooter.

5) This Has Become All Too Common

Texting those at the venue, family members provided advice with one noting that this has become the new "normal."

6) Those Who Could Ran

In this longer version of a video taken from the ground level, the last 15 minutes show that people get up and run when there is a slow moment in the shooting.

7) From Above It's Pandemonium

Views from a balcony show the crowd stampeding.

8) Family Members Reacted From Afar

Those who heard from loved ones at the scene were on social media, just as afraid.

9) People Duck & Hide

Sam Perry on YouTube

This video, compiled from Snapchat shows that the first reaction of many is to get as low as possible. Then they jump over barriers to get away.

10) One Of The Performers Tweeted To His Daughter

Owen's daughter, Pearl, was who he sent his love to.

11) It's Hard To Tell Who's Injured

One man tells his friends, "We can't go yet."

12) The Screams Of Terror To Leave

"Come on, let's go!" shouts one.

13) Survivors Were Shocked

People who made it away from the shooter acknowledged what just happened in the aftermath.

14) From Other Nearby Hotels, It Was Clear Something Was Up

This Twitter user responded to a local news tweet with video from his hotel, the Bellagio.

15) Witnesses Uploaded What They Saw While Running

In this video, a man describes seeing a girl near him get shot in the head.

16) Shots Can Be Heard Far Down The Strip

As far as the Luxor, you can make out the shots.

17) Live Video Uploads Explore The Strip

In this video, originally uploaded to Periscope, you can see the aftermath on the Strip, as those nearby try to make sense of what has just happened.

18) Another Performer Asks For Prayers

The Josh Abbott Band was also performing at the festival, and the lead singer tweeted out a call for prayers.

19) Volunteers Drove Injured To The Hospital

In this video, people volunteer to use their truck to take victims to the hospital. You can see people being transported on metal barricades turned sideways for lack of a better option.

20) Some Fled From The Hotel Too

This Twitter user describes fleeing the Mandalay Bay when the shots broke out. "Most scary moment in my life," he wrote.

21) Gunshots Heard From The MGM, Too

Two guests at the MGM comment on the gunshots outside. You can also hear police sirens. It's more than a mile down the Strip from the Mandalay Bay.

22) For Many, The Goal Was To Hide

Someone told this concert-goer that the best bet was to lie under a trailer.

23) Those Filming From Above Were Nearly Hit, Too

This video, remarkably clear, was taken from above the crowd. It shows that at a certain point the person filming had to duck for cover as the bullets reached the balcony seating area too.

24) At The Concert's Edges, The Fear Is Still Real

This mixture of SnapChat videos shows that there's still plenty to be feared even far out from the main area, where most of the crowd was standing. People are hiding behind food trucks and other obstacles between them and the shooter.

25) This Angle, From Further Back, Shows The Concert Come To A Stop

People pretty far back are taping the show when it stops. Someone says they think they heard gunshots and then people start telling others to get down. Then, as they flee, gunshots break out again. Video isn't visible after a while, but you can hear them shout to others, "Don't push, don't push!"

26) A Close-Up Of Those Huddled Together

People were huddled together on the ground as the shots rang out.

27) People Stream By

People are running by as someone off screen asks, "Why are people laying on the ground? Why are people laying on the ground?"

28) The Sudden Change In Atmosphere Is Remarkable

These festival-goers are further back from the main stage, dancing, until all of a sudden the shots break out.

29) Is It Gunfire Or Fireworks?

"We're going to get trampled if we don't go," one festival-goer says as everyone on video tries to decide what is happening. Somebody later in the video claims it's fireworks.

30) Views Of The Strip Afterwards

Eery canned music plays out from speakers at a hotel down the Strip. The road is closed off to traffic.

31) Scenes Around Hospitals Grew Tense Too

Police shut down traffic around the area hospitals, keeping routes clear for traffic of ambulances and others transporting the injured.

These are just some of the videos that were likely taped on Sunday night. Even more may still be on the phones of concert-goers who are too shaken to share on social media. If you're someone with film or video of the attack, make sure that you share it with the Las Vegas Police Department. They're asking for it.

"Anybody that may have cell phone video or any type of video that would be of benefit to the investigation, please respond to the LVPD HQ and we will take custody of that video," Sheriff Joe Lombardo said at a press conference early Monday.

Make sure to share any video you may have taken at the scene — even if rewatching it is as difficult as what you've seen here.