The U.N. human rights chief on Friday denounced what he described as gang rapes of women in Burundi by security forces, torture and signs of ethnic repression in nine months of simmering violence in the central African nation.
President Pierre Nkurunziza's decision to seek a third term last year has left Burundi on the brink of civil war.
On Friday, a court in Burundi sentenced four military generals who were the alleged leaders of a failed coup to life in prison. Cyrille Ndayirukire, Zenon Ndabaneze, Juvenal Niyongabo and Helmenegilde Nimenya had been among more than 20 former military officers and soldiers put on trial for their alleged roles in the May coup.
The office of U.N. rights chief Zeid Raad al-Hussein's said in Geneva on Friday that 432 people have been killed in violence since April 26.
Zeid said his office is analyzing satellite images to shed light on allegations about the reported discovery of nine mass graves. His office also cited growing signs that Tutsis were being targeted in the Hutu-majority country that is next to Rwanda.
"All the alarm signals, including the increasing ethnic dimension of the crisis, are flashing red," he said.
He also called for an urgent investigation into the events that took place in Bujumbura, the capital, on Dec. 11 and 12, including the reported existence of at least nine mass graves.
In coordinated attacks, gunmen stormed three military installations in Burundi on Dec. 11. The next day, The Associated Press reported at the time, 28 people were found shot dead in three neighborhoods. An eyewitness told AP some of the dead had their hands tied behind their backs. Another witness blamed government security forces saying they went after the victims in door-to-door searches.
In his statement, Zeid referred to "large-scale human rights violations" that occurred in the immediate aftermath of the Dec. 11 attack.
"The increasing number of enforced disappearances, coupled with allegations of secret detention facilities and mass graves is extremely alarming," he said.