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HOUSTON (NewsNation Now) — The chief of the Houston Police personally visited Travis Scott before the deadly concert that left eight people dead and dozens more injured to voice concerns about the crowd ahead of the event.

According to a statement released on Twitter, Chief Troy Finner spoke with Scott and his security chief to convey he had “never seen a time with more challenges facing citizens of all ages, to include a global pandemic and social tension throughout the nation.”

The statement confirmed a report by the New York Times, which said Finner expressed his concerns about the energy of the crowd after a rowdy festival two years ago.

Finner’s statement also says he asked Scott and his team to “work with (the Houston Police Department) for all events over the weekend and to be mindful of his team’s social media messaging on unscheduled events.”

Finner called the meeting “brief and respectful.”

City officials Monday were in the early stages of investigating what caused the pandemonium at the sold-out Astroworld festival, an event founded by Scott. About 50,000 people were there, and eight died. Two of them were teenagers.

Investigators are expected to examine the design of safety barriers and the use of crowd control in determining what led to a crush of spectators.

Authorities planned to use videos, witness interviews and a review of concert procedures to figure out what went wrong Friday night during a performance by Scott. The tragedy unfolded when the crowd rushed the stage, squeezing people so tightly they couldn’t breathe.

The dead, according to friends and family members, included a 14-year-old high school student, a 16-year-old girl who loved dancing and a 21-year-old engineering student at the University of Dayton. The youngest was 14, the oldest 27.

Houston officials did not immediately release the victims’ names or the cause of death, but family and friends began to name their loved ones.

On Monday, Variety reported that Scott will be issuing refunds to all attendees of the festival and he won’t be performing at an upcoming Las Vegas festival this weekend.

Over the weekend, a makeshift memorial of flowers, votive candles, condolence notes and T-shirts took shape outside at NRG Park.

Thirteen people remained hospitalized as of Sunday evening. Their conditions were not disclosed. Over 300 people were treated at a field hospital at the concert.

Billy Nasser, 24, who had traveled from Indianapolis to attend the concert, said about 15 minutes into Scott’s set, things got “really crazy” and people began crushing one another. He said he “was picking people up and trying to drag them out.”

Nasser said he found a concertgoer on the ground.

“I picked him up. People were stepping on him. People were like stomping, and I picked his head up and I looked at his eyes, and his eyes were just white, rolled back to the back of his head,” he said.

Contemporary Services Corp., headquartered in Los Angeles, was responsible for security staff at the festival, according to county records in Texas. Representatives for the company — which advertises online as being “recognized worldwide as the pioneer, expert and only employee owned company in the crowd management field” — did not immediately respond to emails and phone messages seeking comment.

Houston police and fire department officials said their investigation will include reviewing video taken by concert promoter Live Nation Entertainment, as well as dozens of clips from people at the show.

Officials also planned to review the event’s security plan and various permits issued to organizers to see whether they were properly followed. In addition, investigators planned to speak with Live Nation representatives, Scott and concertgoers.

Izabella Ramirez of Texas City was celebrating her 21st birthday and said that once Scott came on stage, no one could move.

“Everybody was squishing in, and people were trying to move themselves to the front. You couldn’t even lift up your arms,” Ramirez said.

Ramirez said a security guard pulled her over the barricade, while her date, Jason Rodriguez, lifted her up.

“Everyone was yelling for different things. They were either yelling for Travis or they were yelling for help,” Rodriguez said.

On video posted to social media, Scott could be seen stopping the concert at one point and asking for aid for someone in the audience: “Security, somebody help real quick.”

An aerial shot from a video showed a tightly knit tangle of concertgoers about 18 minutes into footage that was uploaded by a YouTube user but later removed for copyright violation by Saturday morning.

“For everybody watching at home right now, I want everybody to feel how we do it in Houston real quick,” Scott told the audience moments before the tragedy unfolded, according to video of the concert posted online.

“I wanna see some ragers, man. Who wanna rage?” Scott called out to the audience less than a half-hour into his performance, according to the videos of the concert.

Experts who have studied deaths caused by crowd surges say they are often a result of too many people packed into too small a space.

One of the first of many expected lawsuits was filed Sunday in state courft in Houston on behalf of a man injured in the crush of people. Attorneys for Manuel Souza sued Scott, Live Nation and others, saying they were responsible.

In a tweet posted Saturday, Scott said he was “absolutely devastated by what took place.” He pledged to work “together with the Houston community to heal and support the families in need.”

The Associated Press and Reuters contributed to this report.