Burundi’s President Pierre Nkurunziza has died of a heart attack aged 56.

The statement posted on social media said the president was admitted to a hospital overnight on Saturday after not feeling well. He appeared better on Sunday but “to very great surprise” his health abruptly worsened on Monday morning, and several hours of effort failed to revive him.

Burundi’s government has declared a week of mourning.

Mr Nkurunziza’s death comes weeks before president-elect ruling party candidate Evariste Ndayishimiye was expected to be sworn in after winning the May election.

Mr Nkurunziza addressing the United Nations in 2011
Mr Nkurunziza addressing the United Nations in 2011 (AP/Jason DeCrow, File)

Despite the government’s statement, some in Burundi wondered whether Mr Nkurunziza died of Covid-19 instead.

The government has downplayed the virus and held the election and large campaign rallies in spite of the threat.

Authorities kicked out the World Health Organisation’s top official in the country just days before the election after the WHO raised concerns about crowded rallies. The country has 83 virus cases.

Mr Nkurunziza took office in 2005, chosen by MPs to lead the East African nation after the 1993-2005 civil war killed about 300,000 people. The peace process known as the Arusha Accords specified that a president’s term can be renewed only once.

But Mr Nkurunziza, who won a second term in 2010, announced he was eligible for a third term in 2015 because he had not been chosen the first time by universal suffrage.

The deadly turmoil that followed badly damaged ties with the international community, and Burundi became the first country to leave the ICC after it started investigating allegations of abuses. The United Nations human rights office reported more than 300 extrajudicial killings and was later kicked out of the country.

Pierre Nkurunziza
Mr Nkurunziza survived a coup attempt in 2015 (AP/Marc Hofer, File)

Burundi’s government has denied allegations it targets its people, calling them malicious propaganda by dissidents.

Mr Nkurunziza survived a coup attempt shortly after the 2015 vote. International donors cut support, leaving the government struggling.

Many Burundians were surprised when the president announced in 2018 that he was serving his last term. The government approved legislation meant to bestow upon Mr Nkurunziza the title of “paramount leader” once he stepped down.

Mr Nkrurunziza “leaves behind a legacy of ruthless repression,” said Lewis Mudge, Central Africa director at Human Rights Watch. “He ruled through fear to erect a system synonymous with the worst human rights abuses: extrajudicial killings, torture, disappearances, and the systematic crushing of dissent.”

Burundi must investigate the crimes committed during Mr Nkurunziza’s rule, said Mr Mudge. “As long as these abuses go unpunished,” he said, “this dark legacy will hang over Burundi for many years to come.”