Police officer Ahmed Nur says Monday's fighting began when police executed a plainclothes soldier they suspected of being an Islamist insurgent. Nur says the soldier's colleagues arrived at the scene of the shooting in Benadir market and began attacking the police.
An Associated Press reporter saw 16 bodies at Medina hospital in Mogadishu. Some were wearing uniforms. Three of the victims were women. Hospital director Mohamed Yusuf says 30 people were wounded.
The killings underscore the lack of discipline or command of Somalia's armed forces after 20 years of civil war.