Soldiers direct Burundi civilians to cover as gunfire is directed toward a school where voters were gathered in December.

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Mass graves, sexual assaults by soldiers reported in Burundi, U.N. human rights official says

Newest violence may be a response to mid-December clashes between citizen and the military

CNN  — 

The U.N. human rights chief on Friday called for an investigation into new reports of mass graves and soldiers raping women during home searches in the central African nation of Burundi.

Nine mass graves holding 100 bodies total have been found, including one on a Burundi army base, said U.N. High Commissioner for Human Rights Zeid Ra’ad Al Hussein. Thirteen cases of sexual violence against women have been reported, he said.

Witnesses said the army carried out retaliatory attacks after street violence in mid-December. Zeid said those clashes “appear to have triggered new and extremely disturbing patterns of violations.”

Eighty-seven people were reported killed in the violence last month in the capital of Bujumbura.

Zeid said he’s heard reports of kidnapping, secret detention centers and mass graves.

“My office is analyzing satellite images in an effort to shed more light on these extremely serious allegations,” Zeid said.

Zeid said the sexual violence occurred in neighborhoods perceived as supportive of opposition forces.

“The pattern was similar in all cases: Security forces allegedly entered the victims’ houses, separated the women from their families, and raped – in some cases gang-raped – them,” Zeid said.

“New cases of sexual violence have continued to emerge since mid-December, including the reported rape of five women in a single house during a search operation in Bujumbura Mairie province.”

Zeid said reports of torture also are increasing.

Burundi has experienced months of violence since President Pierre Nkurunziza announced in April that he would run for a third term. That seemed to be a clear violation of the agreement that ended the country’s civil war and Burundi’s Constitution. He won re-election in July.

The subsequent unrest has left scores dead and caused more than 170,000 people to flee the country.

In the country’s civil war, which lasted from 1993 until 2003, an estimated 300,000 people were killed. Burundi has about 10 million people.