AlterFest is now implementing a new curfew following an apparent "teen takeover" during Saturday evening's festivities.
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Archbishop Alter High School explained on social media that a large group of teens showed up at AlterFest "in what appeared to be connected to the recent 'teen takeover' trend."
Festival organizers said everyone was safe, but the incident led them to limit admission to guests ages 21 or older for the remainder of the evening.
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The curfew will also be in effect on Sunday starting at 9 p.m. At that point, anyone under the age of 21 must be accompanied by a parent or guardian.
"The safety of our students, families, volunteers and guests is always our highest priority. We are grateful to the Kettering Police Department, our security team, volunteers and festival staff for their quick response and continued efforts to keep our community safe," the post read.
The "teen takeover" trend, as CBS News reported, is when large crowds of young people gather in public places. Some events have ended in violence and arrests.
One "teen takeover" on the Fourth of July in Florida ended with seven people being shot. A 19-year-old was killed, CBS News reported.
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