Officials in Somalia say insurgents have killed two people and wounded two others in an attack on an army camp near Baidoa, the home of the transitional parliament.
The Islamist insurgent group Shabab claimed responsibility for the attack on the Daynunay military base.
Two days ago, Shabab insurgents fired mortars at the presidential palace and airport in Baidoa, killing at least two soldiers and wounding seven.
Somali's government dismissed that attack as a publicity stunt for the insurgent group, and said that Baidoa is functioning and safe.
Insurgents have briefly overrun more a dozen towns in Somalia in recent months in their fight against the interim government and its Ethiopian military allies.
Ethiopian troops entered Somalia two years ago to help the interim government fight an Islamist movement that was threatening to take over the country.
Somalia has been continuously torn by conflict since the fall of the last stable government in 1991.
Some information for this report was provided by AFP and AP.