For Switzerland such a devastating and lethal fire in a business establishment is quite unusual to happen! About "40 people killed and injured 119, many of them severely" (Source)
Apparently, it was a bar has two-levels on the ground floor and in the basement.
How overcrowded was the bar at the time the fire broke out? Were the managers/owner of this bar culpable.
There was at least one news report that emergency exits were blocked.
Did this establishment not have fire sprinklers or did they not work properly?