The third day of Lollapalooza brought reports Saturday afternoon of crowds of people breaching the fencing perimeter at various locations around Grant Park.
Reports suggested people were roaming as they picked the location of which they wanted to strike.
“While the vast majority of those attempting to breach the perimeter fencing throughout the weekend have been unsuccessful, there have been some cases this afternoon where individuals made unauthorized entry into the park,” read a statement from the city’s Office of Emergency Management.
The office released arrest numbers for the previous day, saying nine people had been arrested for various offenses, including theft and possession of a controlled substance.
Meanwhile, paramedics transported 38 people to area hospitals.
The festival will re-open for its final day Sunday.