CHICAGO — Authorities say a 16-year-old boy has died after attending the Lollapalooza music festival in Chicago.

Police and the medical examiner’s office identified the teen as Evan Kitzmiller of Mundelein, a Chicago suburb. He was found unresponsive Sunday night, the last day of the weekend festival, and pronounced dead at a hospital.

Investigators didn’t release details about his death. But Kitzmiller’s mother says her son had a seizure and his heart stopped.

Melissa Stratton of Chicago’s emergency management office says officials are saddened by the death, and that safety and security are priorities. A statement from Lollapalooza says the teen and his family “are in our thoughts.”

The event drew hundreds of thousands of people to downtown Chicago’s Grant Park.