Initial reports to police indicate that nine people, including four attackers, were killed after gunmen in military uniforms attacked the house of the former Somali parliament speaker and current president of the newly established southwest regional administration, said Col. Mahad Abdi, a Somali police officer.
The attack began when a car bomb detonated at the gate of the state palace in Baidoa city, some 250 kilometers (155 miles) northwest of the capital, Mogadishu.
Heavy gunfire broke out between Somali troops backed by Ethiopian forces inside the house of the regional president, Sharif Hassan Sheikh Aden. Explosions and gunfire were still going on over an hour after the initial assault, Abdi said.
Al-Shabaab claimed responsibility for the attack.
A broadcast by the group's official radio station, Andulus, said that Al-Shabaab gunmen had entered the regional president's house and killed seven Ethiopian soldiers.
The African Union's special representative for Somalia, Ambassador Maman S. Sidikou, condemned the attack, saying it had targeted troops who have worked to restore peace to Baidoa.
"I am deeply saddened by news of the attack in Baidoa this morning," he said in a statement released by AMISOM, the African Union mission to Somalia.
Sidikou said he had also received reports of an attempted attack at a Mogadishu hotel Wednesday night.
"These are desperate attempts by Al-Shabaab to seek relevance, following the massive defeats they continue to suffer from the Somali National Army working together with AMISOM troops," he said.
Al-Shabaab started with a goal of waging a war against the Somali government in an effort to implement a stricter form of Islamic law, or Sharia.
It has since shifted focus to terrorist attacks in Somalia and beyond, even calling, in a video released last month, for attacks on shopping malls
in Canada, the United Kingdom and the United States. U.S. authorities downplayed the threat.