A suicide car bomber thought to be targeting Abdi Fatah Gesey, a former governor, has killed at least 12 people, including Somali government soldiers and civilians, in the south central town of Baidoa.
"A car bomb killed 12 people including government forces and residents," Captain Nur Aden, a police officer, told the Reuters news agency by telephone from Baidoa on Monday.
"The car bomb was targeted at the former governor of Bay region who was by then in a local bank opposite the cafeteria.
"His [ Gesey's ] cars and others which were also parked there were destroyed. Some of his bodyguards were seriously injured. Most of the people who died were residents who were in the cafe."
There was no immediate claim of responsibility but al-Shabab fighters have carried out a string of bombings and vowed to overthrow the war-torn country's internationally-backed fragile government.
The town, about 250km southwest of the capital Mogadishu, which is under the control of government troops backed by African Union forces, was wrested off al-Shabab two years ago.
Recent al-Shabab attacks have targeted key areas of government or the security forces, in an apparent bid to discredit claims by the authorities that they are winning the war against the armed group.
The capital Mogadishu has been hit by a series of suicide bomb attacks in the past few months, claimed by the group, which has waged a sustained campaign even after being pushed out of the city in mid-2011.
Somalia's government is struggling to impose any sense of order, more than two decades after the fall of Mohamed Siad Barre tipped the country into chaos.