Authorities say an incident at rapper Travis Scott's Astroworld Festival in Houston, Texas, killed eight people and wounded numerous more on Friday night.
At either 9 p.m. or 9:15 p.m., the audience "began to push toward the front of the stage, which generated some fear," according to Houston Fire Chief Sam Pea, who spoke at a news conference early Saturday morning.
Seventeen people were sent to hospitals, according to Pea, with 11 of them suffering from cardiac arrest.
He subsequently added that authorities removed 23 individuals for "different medical difficulties" throughout the day, including before the "mass casualty event," and that more than 300 patients were evaluated at the field hospital on site during the day.
Officials won't know the cause of death for the "confirmed" deceased until the medical examiner's inquiry is concluded, according to Pea.
Officials said they don't know what happened, but the situation is being investigated, including who died.
"It seems like it happened with just over the course of a few minutes. Suddenly we had several people down on the ground experiencing some type of cardiac arrest or some type of medical episode," said Houston police Executive Assistant Chief Lt. Larry Satterwhite. "So we immediately started doing CPR and moving people right then."
A swarm of individuals stormed the perimeter of the venue, NRG Park, earlier in the day, but Houston Police Chief Troy Finner claimed during the news conference that the two events are unrelated.
Finner also warned the public against forming assumptions until the inquiry is complete, stating that police have "heard reports" of individuals being injected with narcotics, "therefore I want to investigate all that."
Officials said there was an attendance of about 50,000 people at the festival.
Harris County Judge Lina Hidalgo said some of the victims who were transported were as young as 10 years old.
Families who are looking for people who attended the concert that there is a reunification center at 8686 Kirby at the Wyndham Houston near NRG Park .
"Tonight is about that. Is about connecting families with the information that they need," Hidalgo said.