Austrian judges have ruled that a man who kept his daughter captive for 24 years, raped her thousands of times and fathered seven children with her, can be moved from psychiatric detention to a regular prison.

The decision on Monday was the latest in a legal back-and-forth over Josef Fritzl’s future.

The state court in the town of Krems said in a statement that the 89-year-old can be moved as he no longer poses the kind of danger that requires keeping him in psychiatric detention.

The decision was based on an April 30 hearing with Fritzl, as well as reports by forensic and psychiatric experts.

Because of Fritzl’s advancing dementia and physical decline, psychiatric detention is no longer necessary for his “combined personality disorder” as there is no longer a danger of Fritzl committing serious crimes, the court said.

The court said Fritzl can be moved to the prison for a 10-year trial period but that he cannot be released from detention altogether.

Prosecutors appealed an earlier decision in January that Fritzl could be moved to a regular prison, and both sides are also entitled to appeal the latest decision.

Fritzl’s crime came to light in 2008 and he was sentenced in 2009 to life imprisonment for committing incest, rape, coercion, false imprisonment and enslavement of his daughter, and negligent homicide of one of his infant sons.

Fritzl became known as the “Monster of Amstetten” after the northern Austrian town where he locked up his then-18-year-old daughter in a sound-proofed basement of his house in 1984.

Over the next 24 years, he repeatedly raped her and fathered seven children with her, one of whom died.