The UN-backed court for Rwanda has acquitted on appeal former paramilitary police chief Augustin Ndindiliyimana and ex-elite battalion commander Francois-Xavier Nzuwonemeye of charges related to the 1994 genocide.
The Arusha, Tanzania-based International Criminal Tribunal for Rwanda (ICTR) reduced the sentence of a third officer Innocent Sagahutu, a squadron commander in the elite reconnaissance unit, from 20 years behind bars to 15.
The ICTR said it would hand down its decision on a fourth officer, former army chief Augustin Bizimungu, at a later date.
The court had in May 2011 sentenced Ndindiliyimana to 11 years imprisonment for genocide crimes, a term he had already served in preventive detention since his arrest in Belgium in 2000.
Nzuwonemeye and Sagahutu had both been sentenced to terms of 20 years for crimes against humanity and war crimes.
Bizimungu had been sentenced to 30 years in prison for crimes of genocide, crimes against humanity and war crimes.
The UN-backed court was set up to try the alleged masterminds behind the genocide, in which an estimated 800,000 people, the overwhelming majority of them ethnic Tutsis, were killed.
Other perpetrators have been tried before other jurisdictions, either in the formal court system in Rwanda or before thousands of grassroots tribunals called gacacas.
