Martin, 52, was convicted of helping Dutroux hold six young girls prisoner in the 1990s, and of complicity in the deaths of two eight-year-old girls – Julie Lejeune and Melissa Russo – who died of starvation in Dutroux's dungeon.
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Dutroux, who also raped his victims, and killed two others, is serving a life sentence. Martin, meanwhile, has spent 16 years in prison, after being sentenced to 30 years, and refused parole three times.
AFP reported that the court's decision to grant Martin "conditional release" comes after the Clarisses convent, in central Belgium, agreed to take her in.
The convent is not in a region where the relatives of the victims live, and Martin has been ordered to "keep her distance" from the victims' families.
However, Jean-Denis Lejeune, father of Julie Lejeune, was critical of the court's decision – and the proximity to his home from where Martin will live, the BBC reported.
"No-one has consulted us, and now she will be living as a virtually free woman just 60 kilometers away,” he said. "Legally we are powerless to do anything about this. The rights of the victims' families are being trampled all over by the law."
French authorities last year blocked a bid for Martin to be released to a convent in northern France.
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