In 2002, Ndazigaruye had been acquitted of charges of genocide and crimes against humanity.
On Wednesday, another prosecutor counsel, André Bimenyimana, was also condemned to life in prison.
Hailing from Ruhengeri Prefecture, Cyprien Ndazigaruye, 55, was found guilty of "rapes, incitement to commit genocide, supervision and execution of genocide, installation and supervision of roadblocks, criminal conspiracy and complicity in murders of Tutsis in Nyakabanda", a sector in Kigali.
Valerie Bemeliki, a former anchorwoman at the extremist radio RTLM, was among the prosecution witnesses. She was herself condemned for publicly inciting people to slay Tutsis.
According to the ruling, Ndazigaruye used to make phone calls to the RTLM during the genocide, indicating where Tutsis were hiding. He was also making a profit by supplying food to the Rwandan Armed Forces (RAF).
© Hirondelle News Agency