Three men in their early 20s have been found dead of suspected carbon monoxide poisoning at a country music festival in Michigan.

The men were found dead on Saturday afternoon in their travel trailer on the campgrounds at Michigan’s Faster Horses Festival. Alongside them were two more men who were alive but unresponsive and in critical condition – they were rushed to a local hospital by ambulance.

The tragedy is suspected to be the result of carbon monoxide poisoning. The Lenawee County Sheriff’s Office said in a statement: “According to Sheriff Investigators, the caller was a friend of the five males and became concerned when he had not heard from them. This tragic incident is being investigated as a suspected carbon monoxide exposure from a generator located very near the travel trailer.”

Meanwhile, the Michigan State Police have also been investigating a separate death. In a series of tweets, their investigation is into the death of 30-year-old Melissa Donna Havens, whose body was discovered early on Saturday morning on Faster Houses Festival grounds. Police have not yet announced the cause of death.

The event kicked off on Friday (July 16) and closes on Sunday night, capping off the three-day festival with a performance from headliner Jason Aldean. Earlier in the weekend, Thomas Rhett and Luke Combs each headlined the event’s main stage for a night. Other performing acts at Faster Horses Festival in 2021 include Jon Pardi, Kelsea Ballerini, Jimmie Allen, Riley Green and more.