“This tragic incident is being investigated as a suspected carbon monoxide exposure from a generator located very near the travel trailer,” the sheriff’s office said on Twitter.
Separately, state police reported the death of a 30-year-old woman, Melissa Havens of Croswell.
The cause and manner was unknown, state police said, although investigators were looking for a suspect.
“Detectives want the public to know there is no danger or threats to people attending” the music festival, state police said.
The three-day festival is scheduled to conclude Sunday. Its headliners include Luke Combs, Thomas Rhett and Jason Aldean.
