The morning attack began when a suicide vehicle bomber detonated at the gates of the interior ministry compound, which is close to the presidential palace and parliament headquarters and also holds the security ministry, police Capt. Mohamed Hussein told The Associated Press.
The minister declined to say how many people were killed in the attacks.
The ongoing threat from what has become the deadliest Islamic extremist group in sub-Saharan Africa has hurt efforts to strengthen Somalia's fragile government and stabilize the long-chaotic Horn of Africa nation.
"In the first phase, we carried 13 injured people from near the two blast scenes", Abdikadir Abdirahman, director of the Amin Ambulance emergency service, told Reuters on Saturday.
The al-Qaida linked al-Shabaab militants have claimed responsibility for the latest attack in the capital Mogadishu.