Frontier City kicked off the weekend with Fright Fest, but chaos broke out instead on Saturday night.
There were several original rumors that a stabbing occurred, but Oklahoma City Police said that was not true.
The OCPD said the park was shut down and evacuated early because people were fighting.
Frontier City staff told News 9 that guests are screened for "banned items" before entering the park, and that the park works closely with the OCPD.
The park also said it has a zero-tolerance policy for unruly behavior.