Local people alleged that an armoured AU Mission in Somalia (AMISOM) convoy opened fire after being hit by improvised explosive devices (IED). The incident occurred in the Huriwa district in the north of the city.

AMISOM said in a tweet that its convoy had "encountered double IED explosions in the Soqola area" -- part of Huriwa district. But it made no mention of the shooting, which witnesses said involved Burundian members of the force.

Dozens of angry demonstrators took to the streets of Huriwa, burning tyres and calling for the killers to be brought to justice.

"These innocent victims have been killed by the Burundian soldiers without reason and we are asking the government to respond to this oppression," said Mohamed Warsame, a relative of one of the victims.

Some local people threatened to take matters into their own hands.

Xasan Ugaas Maxamed, a traditional elder warned: "If the government does not act in regard of this incident, we will not live side by side with Burundian soldiers in harmony, and we know how to fight."

One protestor, Abdulahi Mohamed, said: "We were protesting in solidarity with the victims and we need justice for these innocent victims, if nothing is done, we will take justice with our own hands."

Neither AMISOM nor Somalia's internationally backed government were available for comment on the incident.