We show that the "puzzling" chemical composition observed in the extremely metal-poor star HE 0107-5240 may be naturally explained by the concurrent pollution of at least two supernovae. In the simplest possible model, a supernova of quite low mass (～15 solar mass) underwent a "normal" explosion and ejected ～0.06 solar mass of ~(56)Ni while a second one was massive enough (～35 solar mass) to experience a strong fallback that locked in a compact remnant all the carbon-oxygen core. In a more general scenario, the pristine gas clouds were polluted by one or more supernovae of relatively low mass (less than ～25 solar mass). The successive explosion of a quite massive star experiencing an extended fallback would have largely raised the abundances of the light elements in its close neighborhood.
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