A trial could be under way by fall or early winter, an Austrian courts spokesman told The Telegraph (Britain) Wednesday, adding that intensive preparations are already ongoing.

Prosecutors say Fritzl, 73, has already confessed to keeping his daughter Elisabeth locked up in a windowless cellar beneath their home in Amsetten, Austria. But they're also pushing to have Fritzl tried for murder as well, the Telegraph said, in the death of one of Elisabeth's seven children.

The Fritzl survivors, including Elisabeth, Fritzl's wife Rosemarie, 68, and Elisabeth's children Stefan, 18, Lisa, 15, Monika, 14, Alexander, 12, and Felix, 5, all are reported to be improving "faster than expected," the newspaper said.