Prosecutors have appealed a court ruling that cleared convicted serial rapist Joji Obara of charges that he attacked and killed Briton Lucie Blackman, a court official said Tuesday.

Obara, a wealthy real estate developer, was convicted of nine rapes and sentenced to life in prison on April 24 after a six-year trial at the Tokyo District Court. Among the rape victims was an Australian woman, Carita Ridgway, who died after she was drugged and attacked in 1992.

But in a decision that triggered outrage in Britain, the three-judge panel dismissed all charges related to Blackman's killing in 2000, saying there was no concrete evidence linking Obara to her death.

The prosecutors filed their appeal Friday. Obara filed his right after the ruling.

Blackman's family had said they would push prosecutors to appeal, denouncing them for failing to present crucial evidence at the trial and saying the former flight attendant had been "robbed of her justice."

The sordid details of Obara's attacks shocked the public. Obara preyed on women working in nightclubs, inviting them to his condo and plying them with drug-laced drinks to incapacitate them before raping them. He videotaped many of his attacks and kept a detailed diary on his victims in a notebook.

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