The invention relates to a method for extinguishing a smouldering fire in a silo by introducing inert gas into the silo. The inert gas is introduced through a venturi-type nozzle above the stored content in the silo with a slow streaming velocity in such a way that mass ratio of the entrained surrounding gas to the incoming liquid inert gas is between 0.5 and 20. Thus a closed inert gas layer is formed above the smouldering fire.