Al-Shabab spokesman Sheik Ali Mohamud Rage said Saturday that militants carried out Friday's attack against Minister Abdishakur Sheik Hassan because he was "an obstacle" to the group's endeavor to topple the government.
Al-Shabab vowed to carry out "brazen attacks deep inside enemy territory."
Hassan was killed in his home, and a female relative was suspected of being the bomber. Rage thanked insiders who he said helped the attack.
Al-Shabab uses suicide bombers to demoralize the government and their African backers.
Somalia has not had an effective government for two decades.
