Between 500 and 2,000 people have been killed in the violence, according to sources such as the United Nations and non-governmental organisations, and nearly 400,000 pushed into exile.
A UN report released on Monday accused Burundi’s government of crimes against humanity, including executions and torture, and urged the International Criminal Court (ICC) to open a case “as soon as possible”.
Here is a summary of key developments in the crisis engulfing the central African country.
– Demonstrations start –
April 25, 2015: Nkurunziza is declared candidate for a third term by his ruling CNDD-FDD party. The opposition says the move is unconstitutional and violates a peace deal that ended the 1993-2006 civil war.
The following day thousands of protesters take to the streets across the capital, kicking off six weeks of almost daily demonstrations.
– Failed coup –
May 13: Top Burundian general Godefroid Niyombare announces the overthrow of Nkurunziza hours after the president flies to Tanzania.
The coup attempt fails, with some leaders surrendering and others fleeing.
– Defections, re-election –
June 28: Outgoing parliament head Pie Ntavyohanyuma denounces the president’s “illegal” third term bid and says he has fled to Belgium.
He joins a long list of opposition leaders, journalists, civil society representatives and disillusioned ruling party members who have chosen exile.
July 21: Nkurunziza is re-elected in a vote boycotted by the opposition.
– Targeted attacks –
August 2: De facto internal security chief General Adolphe Nshimirimana is killed in a rocket attack.
August 3: Human rights activist Pierre-Claver Mbonimpa, who publicly opposed Nkurunziza’s bid for a third term, is wounded in gunfire.
August 15: Tutsi Colonel Jean Bikomagu, the former head of Burundi’s army during the 13-year civil war, is assassinated.
December 11: At least 87 people are killed in coordinated attacks by unidentified gunmen on three military sites that trigger a fierce riposte from the security forces.
– ‘Risk of genocide’ –
July 2016: The UN Security Council authorises the deployment of 228 UN policemen but Burundi rejects the resolution.
September 20: UN investigators say Burundi’s government is behind systematic human rights violations, including executions and torture, which amount to “crimes against humanity”. They warn of a risk of genocide.
October 27: Burundi decides to quite the ICC which has launched a preliminary examination into allegations of murder, torture, rape and forced disappearances.
– Move to ‘violent dictatorship’? –
December 30, 2016: Nkurunziza, hints he might seek a fourth term in office in 2020.
January 1, 2017: The environment minister is killed in Bujumbura.
January 3: Authorities ban the country’s oldest human rights organisation, the Iteka League.
January 19: Human Rights Watch says young men belonging to Burundi’s ruling party are waging brutal attacks on perceived opponents.
July 4: The International Federation of Human Rights says the regime is moving the country toward violent dictatorship.
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