A 24-year-old man died at the Electric Daisy Carnival in Las Vegas, according to official reports, which were confirmed by the event's promoters.
The name and circumstances of the man's death were not immediately made public by the Clark County coroner. The death occurred Saturday night at the festival, where more than 400 medical calls and 35 arrests were made.
Though it's not clear if the death was heat-related, daytime temperatures at the festival topped 113 degrees Saturday.
In 2014, two attendees died at the festival and a third died shortly thereafter. This year's festival drew an estimated 135,000 fans per night at the three-day event at the Las Vegas Motor Speedway.
In a statement, event promoter Insomniac said, "We extend our deepest condolences to the family and friends of the man who passed away. The health and safety of our fans is Insomniac's first priority and we take every measure to create a safe environment.
"While the cause of this tragedy will take some time to determine, we ask that you keep his loved ones in your thoughts and prayers. Tonight and every night, we ask all of our fans to take care of themselves and one another."