Updated

A U.N. appeals chamber overseeing cases related to Rwanda's genocide on Tuesday reduced one sentence and reaffirmed two others against the ring leaders of the 100-day killing spree in the tiny central African republic some 18 years ago.

The appeals chamber of the International Criminal Tribunal for Rwanda reduced the sentence of former military officer Aloys Ntabakuze from life in prison to 35 years for genocide-related charges.

Ntabakuze was convicted of conspiracy to commit genocide, genocide, complicity in genocide, and crimes against humanity.

Lt. Ildephonse Hategekimana's sentence of life imprisonment was affirmed by the appeals chamber.

Hategekimana was found guilty of genocide in the massacre of civilian Tutsis in Ngoma and of raping Tutsi women.

Former businessman Gaspard Kanyarugika's 30-year sentence was also affirmed by the appeals court on grounds that the defense did not prove beyond doubt that the convict did not commit the 1994 horrendous attacks and killings against ethnic Tutsis.

Judge Patrick Robinson ordered that Kanyarugika be given credit for time served since his 2004 arrest.

At least 500,000 ethnic Tutsis and moderate Hutus were slaughtered during the 100-day genocide in 1994. The tribunal was established in November that year.

The U.N. court has rendered 69 judgments, including 10 acquittals. One trial is pending and 15 cases are still before the appeals court.

The president of the international tribunal, Rachida Khan, told the U.N. Security Council last year that the trial work is expected to be finished by June 2012 and appeals work is on track to be completed by the end of 2014.