Somalia is to set up a regional commission to probe the killing of seven health workers and report publicly within a month.
The head of Hirshabelle state told Reuters on Friday, as the United Nations condemned what it called an outrage.
Masked men abducted the health workers from a healthcare facility in Galooley village, 30 km (19 miles) north of Mogadishu, on Wednesday. Their bodies were found on Thursday.
The kidnapping happened hours after an explosion targeted a Somali military vehicle in the area, a relative of one of the health workers told Reuters, asking not to be identified.
It was unclear if the events were related.
The federal government did not respond to requests for comment.
The al Shabaab Islamist insurgency is also active in the region, but could not be reached for comment.
President Mohamed Abdi Ware of Hirshabelle State in Somalia said he was forming his own commission of inquiry led by the state justice minister.
They will publish their report within a month, he said.
Ware, who previously worked with the Red Cross, said he was outraged.
“I have walked in their shoes as a humanitarian worker,’’ he said. “This is about as personal as it gets to me.’’
Speaking to Reuters, a relative of one of the workers described the abduction, citing witness accounts.
“The health workers were taken out of the centre by masked armed men in military uniform driving a minibus.
They blinded them with their own shirts and tied their hands behind their backs using belts. There was also a civilian who they took from his home,” the relative said.
The bodies were bound and blindfolded, he said, and shot in the head and the heart.
Adam Abdelmoula, the U.N. Humanitarian Coordinator for Somalia, issued a statement saying “I strongly condemn this outrage and await a thorough and transparent investigation”.