'Needle spiking' part of investigation into Astroworld deaths.
A crush of fans pushing toward the stage during rap star Travis Scott's Astroworld music festival in Houston has killed at least eight people and injured dozens more.
City Police Chief Troy Finner said his department has opened a criminal investigation by homicide and narcotics detectives following unconfirmed reports someone in the audience "was injecting other people with drugs".
The disaster unfolded around 9.30pm local time on Friday during the headline performance by Scott, a Grammy-nominated singer and producer, following what police and members of the crowd described as an escalation of unruly behaviour.
JUST IN: Travis Scott shares video addressing the tragedy at Astroworld Fest pic.twitter.com/MSjVpJH3fK— XXL Magazine (@XXL) November 7, 2021
As some in the sold-out audience of about 50,000 surged toward the stage, people began to fall unconscious, some apparently suffering cardiac arrest or other medical issues, officials told reporters outside the venue.
Minutes later the chaos was declared a "mass casualty incident".
"It happened all at once. It seemed like it just happened ... over the course of just a few minutes," said Houston Police's Larry Satterwhite, who was at the front of the event when the situation began.
Satterwhite said he immediately met with promoters and they agreed to halt the show. Officials said the concert was brought to an end by 10.10pm.
Finner said among the "narratives" under review by police were reports suggesting "some individual was injecting other people with drugs".
Read more on 'needle spiking' here.
One report involved a security officer "who felt a prick in his neck" as he was trying to restrain or grab someone and then fell unconscious, only to be revived with a dose of the opioid antidote NARCAN, Finner said, citing an account from medical personnel who treated the officer.