Authorities had to rescue 12 people sleeping in nearby tents, a police spokesperson said, adding that eight people were taken to the hospital for smoke inhalation.
PHOTO GALLERY: Click here to view photos of the Wacken heavy metal festival.
Police believe the fire was arson and the festival organizers have set a €1,000 reward in exchange for the identity of the homegrown pyrotechnics artist.
Some 70,000 metalheads are rocking out to 70 hard rocking bands at the sold-out Wacken Open Air festival in the northern German state of Schleswig-Holstein. Iron Maiden is headlining the self-proclaimed world’s largest metal festival, which invades the tiny town of just 1,900 each year.