Gregoire Ndahimana's family were to be sent to Rwanda
An ex-mayor has denied charges he took part in the 1994 Rwandan genocide when he appeared at a UN-backed tribunal.
Gregoire Ndahimana is accused of responsibility for the massacre of some 2,000 ethnic Tutsis sheltering in a church which was bulldozed.
He was arrested in August during operations against Rwandan rebels in the Democratic Republic of Congo.
The US had offered a $5m (£3.2m) reward for information leading to his arrest, but nobody claimed the money.
Earlier this month Mr Ndahimana was sent from Kinshasa to Arusha, Tanzania, where the International Criminal Tribunal for Rwanda (ICTR) is based.
His wife and five children will be sent to Rwanda, the AFP news agency reported.
ICTR prosecutors believe that almost the entire 6,000-strong population of the town of Kivumu - where Mr Ndahimana was mayor - was killed during the genocide.
Some 800,000 Tutsis and moderate Hutus were slaughtered in the 100-day genocide.
After the 1994 killing spree, some of those responsible fled across the border to DR Congo, sparking years of unrest in the region.