Multiple police departments were called to the fair on Saturday night, May 11, said West Whiteland police.
"A large number of juveniles created a disturbance, which created an unsafe environment for those attempting to enjoy this annual event," police said. Video from the fair showed one person being punched and kicked by at least two others.
WWPD said they are investigating the assault and anyone with information should contact Sgt. McCloskey at jmccloskey@westwhiteland.org.
Fair operator Goodtime Amusements said Saturday night that the event would remain closed "indefinitely."
"Due to out-of-control behavior and the unrest that transpired, the Exton Square Mall Carnival is closed," they wrote on Facebook.
"We appreciate the families that came out to have fun with their families."
By midday Sunday, May 12, police said they had revoked the event's permit.
"The safety of all those attending is primary and foremost in the decision to cancel the Carnival," WWPD wrote in a release.
The fair had been scheduled to continue through May 18.
Fairgoers seeking refunds should contact Goodtime Amusements directly, police added.
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