Man at the "genocide cemetary" of Kigali, Rwanda (file photo)

The appeals' court hearing is the latest chapter in lengthy efforts to bring Rwandan Roman Catholic priest Wenceslas Munyeshyaka and former prefect Laurent Bucyibaruta to trial. Both men have been living in France for years and are accused of participating in the 1994 Rwandan genocide that killed 800,000 people. Father Munyeshyaka had been a practicing priest in a French parish.

French authorities arrested the two men in July, but released them in early August after a local court ruled that arrest warrants from the U.N.-backed International Criminal Tribunal on Rwanda were invalid. They were re-arrested last Thursday, after the Arusha-based tribunal reportedly issued new, more explicit warrants to have them tried in Tanzania.

But Jeanne Sulzer, head of the legal action group of the Paris-based International Federation for Human Rights, believes the two men should be tried in France, which has jurisdiction to do so. She also criticizes the long delay in bringing the two suspects to justice - especially in the case of Father Munyeshyaka.

"France has been condemned by the European Court for Human Rights for the unreasonable delay against Munyeshyaka," said Sulzer. "It has been more than 10 years since the investigation has been opened. What the victims are asking for now is that there is an effective investigation and that this person be prosecuted before an independent and impartial tribunal."

The Rwandan genocide also remains a point of contention between Kigali and Paris, prompting Rwanda to cut diplomatic ties last year. Officials hope relations will normalize under the new government of French President Nicolas Sarkozy.