The African Union said that three civilians were killed and two others injured during a firefight between its forces in Somalia and Islamists from the Al-Shabaab group.
Somali soldiers have vacated at least three of their bases in protest over months of missed pay, a military officer and residents said on Wednesday, in what could be a boost for al Shabaab insurgents.
Somalia's al Shabaab group has taken control of El Bur, a town in the Horn of Africa's semi-autonomous region of Galmudug, after Ethiopian forces left, a government official has said.
At least four soldiers were killed and five wounded on Tuesday when a roadside bomb that Islamist militant group al Shabaab said it planted exploded outside a military camp in a town near Mogadishu, officials said.
A car bomb claimed by al Shabaab Islamist militants killed five soldiers outside the president's palace in the Somali capital of Mogadishu and badly damaged two nearby hotels, police said.
Somalia's al Shabaab Islamist militant group attacked a military base of Ethiopian soldiers serving with an African Union force on Thursday, with both sides saying they had inflicted a heavy toll on their opponents.
Gunmen holed up in a central Mogadishu hotel for more than 12 hours killed at least 10 people in the latest attack in Somalia by the Al-Qaeda group, the Shabaab.
Kenya said a search and rescue operation was underway in Somalia on Sunday as Al-Qaeda-linked militants claimed to have killed over 100 Kenyan soldiers in Friday's attack on an African Union base.