Burundi attacks: 'Mass graves' found after clampdown
8 January 2016 Last updated at 19:40 GMT
Hundreds have died in Burundi since the president announced he would be running for a third term last year.
But evidence is emerging that many of those who died were unarmed, and that they were shot several hours after a rebel attack in December.
The most deadly attack since the crisis began happened on 11 December, when armed insurgents stormed three army barracks.
The government says 87 of them were killed.
Maud Jullien reports.