The cause of the fire could not be determined. One possibility is arson, but an electrical short circuit can not be ruled out.
The fire started in the work area of the central warehouse where some 900 kilos of fireworks were stored. The fire extended to two full containers that were illegally standing outside the building. Because the fire brigade couldn't contain the fire initially, it was able to spread to a third container, which exploded shortly afterwards. A chain reaction of explosions led eventually to the destruction of the firework bunker. As a result the surrounding residential area was virtually destroyed.