Concertgoer Brian Claypool feared for his life Sunday when a gunman opened fire during the final night of the Route 91 Harvest Music Festival in Las Vegas, saying he “didn’t want to die.”

Country music artist Jason Aldean was performing when the gunfire erupted, Claypool said, causing everyone to panic.

“It was pretty eerie because Jason [Aldean] kind of hesitated in his song and I’m thinking, ‘Wow, he’s pretty worried about something’ and then all of a sudden we heard the shots and then I saw him drop his guitar,” Claypool told ABC News today.

PHOTO: People run from the Route 91 Harvest country music festival after gun fire was heard, Oct. 1, 2017 in Las Vegas. (David Becker/Getty Images) More

Claypool said he was sitting in a VIP area near the near the stage when he heard gunshots and began to run.

“I knew something was wrong and then I heard shots fired, just going off like they were right on top of us,” he said. “So I ran to the front of the aisle, laid face down on the aluminum, was pulling people down because I think a lot of folks didn’t realize at that point that the shooting was taking place. They were still sitting up.”

He was among the many concertgoers who were forced to run for their lives late Sunday when the shooter opened fire on the large crowd, killing more than 50 people and injuring at least 400.

“I have to tell you, when I was on that ground, that shooting went on for -- it had to have been 20 or 30 seconds,” he said, describing the first burst of gunfire.

He said he ran into a little room that he described as a production area with about six young girls who were all crying hysterically.

“The hardest for me was -- I saw six young women, they were maybe 20, 22. They were all crying on the ground. I was trying to be calm,” Claypool said while fighting back tears. “But I thought at the moment of the Orlando shooting because we were in this room,” he said of the 2016 Pulse nightclub shooting that left 49 people dead. “We didn’t know where the shooter was. We thought he was going to jump the fence and come in this room and shoot us all. So I didn’t know whether that was the right decision. I’m thinking, ‘Am I gonna die in this room?’

“I didn’t want to die inside of this little room with these girls,” he added. “I rallied everybody out of that room to run north to get away from the shots.”

Eyewitness breaks down describing Las Vegas shooting: “We thought he was just gonna jump the fence and come in that room and shoot us all.” pic.twitter.com/QkHg0n7JQF — ABC News (@ABC) October 2, 2017

Claypool said he saw two people get shot down and spoke to other witnesses who said they watched their friends die.

"It was chaos everywhere" and it was hard to figure out where to run, he said.

Claypool said his attendance at the festival Sunday night was “ironic” because he had originally planned to leave Las Vegas on an earlier flight Sunday evening, skipping the last night of the festival. But he said he changed his mind because his view from the 24th floor of the Mandalay Bay Hotel, which he said was similar to the view the shooter had, was “so beautiful” that he decided to stay one more night.

“I was going to leave and take a 7:50 flight back to L.A.,” he told ABC News. “What’s so surreal about this is, I’m on the 24th floor of the Mandalay Bay. I have the exact view of this lunatic that killed everybody, and I was looking out that window [Sunday] afternoon and I said to myself, ‘This looks so beautiful. It’s such a beautiful setting that I’m going to stay an extra night and not go back.’ And then I go, and people are massacred. Because of that same view that I saw.”

Social media video showed witnesses scrambling to flee the scene as shots rang out. Some people were seen crouching on the ground, stumbling over each other, as others attempted to run.

Claypool said he was able to make it out without physical harm, but added that the images of the terrifying scene will stay with him forever.

“I’m telling you, your life was flashing in front of you,” he said. "The feeling you get is complete helplessness."

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