ARUSHA, Tanzania (AFP) - A UN-backed tribunal convicted a former senior Rwandan army officer of playing a major role in the country's 1994 genocide and sentenced him to 25 years in prison, the court said. The International Criminal Tribunal for Rwanda (ICTR) found ex-colonel Aloys Simba guilty of genocide and extermination during the 100-day massacres in which some 800,000 people, mainly minority Tutsis, were slaughtered by Hutu extremists, it said. The former officer and member of parliament had initially faced four counts but was acquitted on charges and conspiracy to commit genocide and murder, the ICTR said in a statement....