Al-Shabaab militants killed an African Union Mission in Somalia (AMISOM) from Burundi on March 21.
The militants reported the incident, which is yet to be independently verified.
According to the militants, they accosted a group of AMISOM officers on Sunday near Mahaday town.
Mahaday town is close to 120kms to the north of Mogadishu.
Two other AMISOM soldiers from Burundi were injured in the attack.
AMISOM is yet to issue any statement or comment on the incident.