Governor for the Middle Shabelle region, Abdi Jinow Alasow
"There was a heavy explosion, we believe caused by an explosive device [left over from fighting in the area] that they had been playing with," AFP quoted governor for the Middle Shabelle region, Abdi Jinow Alasow as saying on Monday.
"...The death toll could rise as most of the victims have suffered serious injuries " he added.
"I heard a very loud explosion, and minutes later I saw mothers crying," said a local witness.
The incident happened on Monday morning in the restive town of Balad, just 30 kilometers north west Mogadishu, where Somali government forces have recently regained control of the district from al-Shabab fighters.
Somalia has not had an effective central government since 1991, when warlords overthrew former dictator Mohamed Siad Barre.
The weak Western-backed transitional government in Mogadishu has been battling al-Shabab for the past five years and is propped up by a strong African Union force from Uganda, Burundi, and Djibouti.