The 41st edition of ComFest is under way at Goodale Park in Columbus and tens of thousands of people are expected to attend the event.
Police officials told 10TV that they want everyone to obey the law. Authorities say they want to ensure the crowd's safety.
While officers said that they want everyone to have fun, ComFest is not an event where "anything goes."
Special duty and on-duty officers will be working at Goodale Park, and police say they will not tolerate any illegal drug use.
"We don't do anything extra, but we certainly take enforcement action, which by our numbers last year, shows that we do enforce the narcotics laws," said Columbus Sgt. Joe Podolski.
Organizers are also asking people not to bring any coolers or any alcohol into the park. They say there are plenty of food and drink options at the festival.
ComFest runs through Sunday and admission is free.
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