Horrified residents awoke Saturday to at least 39 dead bodies scattered in the streets of the Burundi capital, Bujumbura, a day after coordinated armed assaults on three military installations.

Witnesses and journalists in Nyakabiga, a hotspot neighbourhood for anti-government protests in recent months, reported seeing at least 20 corpses, some apparently shot dead at close range.

One witness described some of the victims as "kids" and said they had been shot execution-style "through the top of the skull".

"It is an absolute horror, those who committed this are war criminals," the witness told AFP.

In the neighbouring Rohero II, at least five dead bodies — again young people — were found on the main road, residents said.

In Musaga, close to a military college that was attacked by armed men early on Friday, a local official said there were more than a dozen corpses in the streets. "I have counted 14 dead bodies with my own eyes," he said, blaming "soldiers and police" for the killings.

Several residents contacted by AFP accused the police of rounding up young men after Friday's attacks and executing them.

"Most of those killed are young heads of households who were at home... it's carnage, there is no other word for it," said an outraged resident of Nyakabiga.

Burundian officials and police could not be reached for comment early on Saturday.

The killings appear to have taken place late Friday, hours after the early-morning assaults on the Ngagara base and a military training college, both in the capital, as well as on a base in Mujejuru, 40 kilometres (25 miles) away.

Burundi's army said 12 gunmen were killed and another 21 captured after the attacks.

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