An officer who witnessed the incident, said it seemed to happen “all at once.”
“It seemed like it happened over the course of just a few minutes,” he said. “Suddenly we had several people down on the ground experiencing some type of cardiac arrest or medical episode and so we immediately started doing CPR and moving people.”. https://www.click2houston.com/news/local/2021/11/06/hfd-responding-to-reports-of-multiple-injuries-at-astroworld-festival/
That's my thought and one of the articles I read said one was 10.