The question is relevant because of parallels to the case of Austrian Josef Fritzl, who imprisoned his daughter in a windowless cellar for 24 years and repeatedly raped her, fathering her seven children. Fritzl was sentenced to life imprisonment two years ago for that crime and for responsibility in the death of one of the children.
But state prosecutor Alois Ebner said Friday that questioning of the 80-year-old's two daughters and other leads had not turned up any indications of offspring.