On Monday, a mortar round crashed into a group of Somali civilians queuing up at one of the entrances of the AU's peacekeeping mission (Amisom) to receive medical treatment from the force's doctors.
"The attack on the compound of the African infidels was carried out by our mujahedins [holy warriors]. It was a successful attack that left many of the enemy doctors dead," al-Shabaab spokesperson Sheikh Ali Mohamoud Rage said.
Officials on the base said at least one Ugandan peacekeeper was killed in the blast. They added that several Somali civilians may have died but could not provide an accurate count.
A civilian source on the base said a total of five people were killed.
