Mountain rescue forces in front of the collapsed rock face.
Helpers are searching through a completely destroyed house. After the catastrophe, the area looked like warzone.
Clearing the area was complicated by the vast number of unexploded munitions.
The train tracks in the area were also destroyed.
100 buildings were destroyed or damaged and more than 200 people were made homeless.
In the following days, a large number of parcels filled with clothes, shoes and other items were delivered to help the people in the area. Additionally, donations of at least CHF 120,000 were made.
A funeral ceremony in which the condolences of the cabinet were expressed to the victims of the catastrophe.
Historic black-and-white picture gallery
The detonation injured several people and killed nine, among them four children. Many houses in the vicinity were completely destroyed.
The series of explosions which shook the valley were so strong that they were registered by the seismological service in Zurich - 115 kilometers away.
Jets of flames, hundreds of metres high, shot up into the night sky. The ammunition and debris that were expelled destroyed up to 100 buildings in the valley. The rock face, in which the ammunition storage room had been located collapsed and 250,000 cubic metres of rock were released. Huge boulders, weighing several tons were thrown across a distance of several hundred metres. Rubble, splinters and the burning remains of ammunition were scattered along a large radius surrounding the explosion.
The catastrophe was one of the worst ever artificial explosions which had ever been caused without the use of atomic weapons. To this day, the cause of the accident remains a mystery.
Translated and adapted from the German by Laura Németh, swissinfo.ch
(Images Walter Studer/Photopress-Archiv/Keystone)