CHICAGO (CBS) — Two people were arrested and 46 were taken to to hospitals on Thursday during the first day of Lollapalooza in Grant Park, according to Chicago Police.

Officials say there were 109,300 people in attendance for the first day of the music fest.

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About 400,000 people are expected to attend the four-day festival.

Friday’s headliner is Bruno Mars.

For more information on the lineup for Lollapalooza, visit lollapalooza.com. 

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