Around one hundred people, many of them teenagers, were hospitalized for drinking too much during a concert headlined by Chance the Rapper in Connecticut Friday night.

Police said that there was "a great deal of tailgating, partying and heavy drinking" at Hot 93.7's Hot Jam Summer concert, where most of those in attendance were in their early 20s or younger, according to the Hartford Courant. The cops issued 50 underage drinking referrals, and had to call in for additional ambulances to take patients to nearby hospitals.

"Drug use [was] a concern, but not as prevalent," Deputy Police Chief Brian Foley told BuzzFeed News. "Heat also played a role—in the 90's, hot cars in hot parking lots, no shade."

The police chief tweeted that there was an "extraordinary number of EMS transports of severe [drinking]," along with vide of the event, which appears to be taking place in a shadeless parking lot.

"A 'typical' concert is around 20-30 transports. 60 would be very bad. We had 70 once and 90 last night," the police chief also told the Courant. Authorities called on additional ambulance providers for help, and sent patients to hospitals in Farmington, Manchester and New Britain.

The event also featured a police unit devoted to stopping underage drinking, courtesy of an “Underage Drinking Enforcement” grant provided by the state Department of Transportation.

Most of those charged with underage drinking were issued court summonses, and are scheduled to appear in a Hartford court this week.