gSeaGen efficiently generates high statistics of the neutrino interaction events detectable in neutrino telescopes. It generate events induced by all neutrino flavours, considering topological differences between track-type and shower-like events. The neutrino interaction is simulated taking into account the density and the composition of the media surrounding the detector. A GENIE-based application, gSeaGen has also been extended to allow simulating atmospheric muons, starting with muons at sea level as generated by CORSIKA (ascl:1202.006).