While waiting to enter the arena, ticket holders picked up metal fences that were meant to keep fans in line ahead of the concert at 8 p.m.
"It's a really intense, aggressive album," said one fan. "People came to the concert really amped up and ready to go crazy. Maybe the people at NRG weren't prepared for that."
Pictures and video shared with ABC13 show fans bypassed security and knocked down metal detectors.
The Houston Police Department even put out a radio call asking for more officers to respond to the incident. They ultimately controlled the incident and said no arrests have been made.
A witness told ABC13 she saw an ambulance was called for someone who had been trampled during the chaos, but no details regarding that were released.
Officials at NRG said ticket holders should seek a refund from where they purchased their tickets.
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