A high-ranking army officer, an ally of the president, was killed Tuesday in the capital, Bujumbura, officials said.
The officer, Lt. Col. Darius Ikurakure, was shot inside the army headquarters, multiple military officials said.
Colonel Ikurakure was commander of Camp Muzinda, in Bubanza Province, a position that put him in charge of security operations in Bujumbura districts seen as hostile to the government.
He was seen as an enforcer, accused of being behind the extrajudicial killings and disappearances of civilians opposed to President Pierre Nkurunziza’s government, said Vital Nshimirimana, a Burundian human rights activist.
Burundi has been volatile since Mr. Nkurunziza announced in April that he would seek a third term, which he eventually won.
Hundreds of people have been killed in the continuing unrest.