The investigators in September 2016 published a report accusing government of gross human rights violations.

The Minister of Foreign Affairs of Burundi, Alain Aime Nyamitwe  in a letter has said that United Nations investigators;  Pablo de Greiff of Colombia, Christof Heyns of South Africa, and Maya Sahli-Fadel of Algeria were no longer welcome in Burundi, BBC reported.

Alain Aime Nyamitwe   in the letter said their investigation published in a UN report, had described "abundant evidence of gross human rights violations" possibly amounting to crimes against humanity, by the government of Burundi and people associated with it. The decision to bar the UN investigators from entering Burundi comes days after government announced plans to withdraw from the International Criminal Court (ICC). Six months earlier, the International Criminal Court reportedly said it would investigate ongoing violence in Burundi.

The investigators in the report said thousands of people had been tortured, suffered sexual abuse or disappeared during political violence, BBC cited. They are also reported to have warned of the danger of genocide from the escalating violence.

Reacting to the government decision, the United Nations spokesman Stephane Dujarric speaking in the headquarters New York on Monday, October 10, 2016, urged Burundi to continue to co-operate with the investigators. BBC quoted him as saying that, "It's critical that Burundi and every other country co-operate fully with UN human rights mechanism and that is including working with those representing it”.