Abstract: Production of at least a gaseous product containing a substantial amount of hydrogen sulphide via a bore-hole from an underground formation containing besides the hydrogen sulphide at least elemental sulphur by(a) injection of a liquid substantially consisting of hydrocarbons into the bore-hole or into the underground formation near to the end of the bore-hole;(b) producing a gaseous and a liquid fraction from the underground formation;(c) separating the gaseous fraction from the liquid fraction;(d) if necessary, separating an aqueous fraction of the product liquid fraction from the hydrocarbons-containing fraction;(e) heating the hydrocarbons-containing fraction preferably in the presence of hydrogen and a hydro-desulphurization catalyst, in order to remove elemental sulphur; and(f) reinjection of at least a part of the thus treated hydrocarbons-containing fraction into the bore-hole or into the underground formation near to the end of the bore-hole.