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This year's Wacken Open Air was struck by tragedy, Contact Music reports, as a man died of carbon monoxide poisoning at the German heavy metal festival.

The victim, whose name has not been released, apparently fell asleep in a canvas tent containing a power generator. He's thought to have inhaled toxic gas, and while medics were called to the scene, they were unable to revive him.

"Unfortunately, we have sad news: We were informed by the German Red Cross that there has been a death at the Wacken Open Air 2012," said organizers of the event, a four-day metal extravaganza that featured such acts as Cradle of Filth (pictured), Sepultura and Ministry.

"We are shocked and send our condolences to family and friends of the deceased," the statement continued.

According to Blabbermouth.net, German authorities have launched an investigation of the incident.