Augustin Bizimungu, commander in chief of the Rwandan army during the 1994 genocide in which 800,000 were killed, has been found guilty and sentenced to 30 years in jail.
Bizimungu, 59, was accused of genocide, crimes against humanity and violating the Geneva Convention but managed to elude justice for years until his arrest in Angola in 2002.
On Tuesday judges at the United Nations-backed International Criminal Tribunal for Rwanda, convened in the Tanzanian city of Arusha, found Bizimungu guilty of genocide and crimes against humanity. His trial had lasted nine years.
The judge said that Bizimungu had complete control over his forces and ordered killings.
Two other Rwandan generals were each given 20-year sentences while a former paramilitary police commander, Augustin Ndindiliyimana, was found guilty but released due to time already served.
Bizimungu is one of the most senior Rwandan officials so far convicted by the tribunal which was set up to try the masterminds of the three month long genocide in which ethnic Hutus massacred their Tutsi neighbours.