The scenery went on fire at a recent Rammstein concert in Riga after some fireworks were let off. A video of the incident was published on YouTube.
Concertgoers said they believed that the fire was part of the German band's show.
The organisers of the concert managed to extinguish the fire.
Rammstein held a concert at the Luzhniki stadium in Moscow in July when the band took to the stage in front of 100,000 fans.