By ELOGE WILLY KANEZA, ASSOCIATED PRESS BUJUMBURA, Burundi — Sep 11, 2015, 3:24 PM ET

Burundi’s army chief survived an apparent assassination attempt Friday by gunmen who attacked a convoy escorting him in the nation’s volatile capital, witnesses and an official said. The military said six people were killed in the attack.

Gunmen wearing military fatigues and riding a pickup truck fired on Maj. Gen. Prime Niyongabo’s convoy as it drove in Bujumbura’s Kinindo neighborhood early Friday, said Anicet Nkunzimana, a witness who lives in the neighborhood. She said there was exchange of gunfire and explosions.

Military spokesman Col. Gaspard Baratuza told reporters in Bujumbura that three soldiers, one civilian and two of the attackers were killed in the incident. Niyongabo was not injured and is now back at work in his office, he said, without elaborating.

Witness Hamissi Misigaro said the vehicle used in the attack was later retrieved from the anti-government stronghold of Musaga. Four men were arrested there following a search operation by security forces, he said.

Niyongabo is believed to have helped foil an attempted coup in May against President Pierre Nkurunziza, who faced deadly street protests over his bid for a third term. Nkurunziza won re-election in July in a vote widely seen as not credible and violence persists in Bujumbura.

In Washington, State Department spokesman John Kirby said the United States condemns the attack on Niyongabo.

“Burundi must step back from the path of violence. The only credible root to stability is a regionally mediated and inclusive dialogue that leads to consensus on a peaceful way forward,” Kirby said in a statement.

In August, a top military general who once led the intelligence services, Adolphe Nshimirimana, was killed in a drive-by shooting in Bujumbura, sparking concerns of revenge killings between regime loyalists and opponents.

On Monday, opposition spokesman Patrice Gahungu was killed by gunmen outside his home in Bujumbura.