This file photo taken on June 8, 2004 shows Michelle Martin, ex-wife and accomplice of paedophile killer Marc Dutroux.

Brussels - Belgian prosecutors have launched an appeal to block the release from prison of the ex-wife and accomplice of convicted child murderer Marc Dutroux.

Michelle Martin, who has been jailed since 1996 and has served half of her 30-year sentence, has been cleared for conditional release. A court in the southern city of Mons ruled on Tuesday that she be released and moved to a convent.

Public prosecutor Claude Micheaux told Reuters on Wednesday that he had launched an appeal shortly after the ruling. “I believe there is a legal problem and we are currently analysing this,” he said.

Martin had been expected to be released within two weeks to be moved to the Clarisse Convent in Malonne, a village 60km southeast of Brussels. Even if the prosecutors' bid is unsuccessful, she could remain in prison for another 30 days pending the court ruling on the appeal.

Dutroux was arrested in 1996 and later found guilty of kidnapping and raping six girls. He killed two of them and left two others to starve to death in a makeshift dungeon.

The case horrified Belgium, and the court's ruling angered the families of victims and dominated the front pages of the country's main newspapers on Wednesday.

“The release of shame,” the French-language daily La Derniere Heure called it in red letters, showing a cropped face of Martin on a black front page. Le Soir called it “the impossible release”. - Reuters