Tomorrowland Unite Spain in Barcelona was forced to evacuate a crowd of about 22,000 people after an enormous fire broke out and engulfed the festival's stage.
Attendees on social media claimed that the stage "exploded" a few hours before Steve Aoki was slated to perform, and early local media reports suggest that pyrotechnics are to blame for the blaze.
Much of the stage seemed to be destroyed by the fire. At the time of reporting, no deaths or major injuries have been reported.
"The firemen's initial hypothesis is that there was an overheating of the material used in the construction of the stage during the presentation of a pyrotechnic spectacle," Globo reports.