Al Shabaab, the Islamist insurgent group that is fighting the UN-backed Somali government, did not immediately claim responsibility.
A military court in the northern Somalian town of Bosaso has sentenced seven suspected al-Shabaab Islamist militants to death.
Relations between the Horn of Africa and the Arabian Peninsula go back centuries, with trade playing a key component in binding their people together.
Thousands of malnourished Somali women and children are fleeing into Ethiopia to escape Islamist militants who are taxing them and seizing their food, animals and land.
The al Qaeda-linked group confirmed the executions, which took place on in Jamame district of lower Jubba region, Somalia.