Vienna: Austrian Josef Fritzl has visited the cellar where he imprisoned his daughter for 24 years and fathered seven children with her, police said on Friday.

Fritzl visited the cellar under police guard on Thursday at the request of his lawyer, police chief Franz Polzer said.

Fritzl, who has been in investigative custody since the case was exposed in April, kept his daughter Elisabeth in a soundproofed basement under his house in the central Austrian town of Amstetten.

"They saw the prison, examined the locks, then they went back to court," Polzer said.

Fritzl has told police the locked door to the cellar would have opened automatically if he had been away for an extended period.

Earlier this year Fritzl's lawyer said his client was "emotionally a broken man" and that it would be hard for him to get a fair trial in front of a jury because of the massive publicity generated by the case.