The African Union peacekeeping mission in Somalia (AMISOM) apologised for accidentally killing four civilians Saturday after soldiers mistook them for Shebab fighters when they failed to stop at a roadblock.
The incident happened in the area of Buulo Mareer in the Lower Shebelle region, 80 kilometres (50 miles) south of the capital Mogadishu.
"A speeding vehicle approached the roadblock and failed to adhere to repeated warnings to stop. Assuming the car to be a Vehicle Borne Improvised Explosive Device (VBIED), the troops opened fire resulting in the death of four occupants of the vehicle," said a statement issued by AMISOM Sunday.
"AMISOM profoundly regrets the loss of civilian lives that occurred during the operation and presents its heartfelt condolences to the bereaved families," said the statement.
The incident has been referred to the African Union commission and an AMISOM inquiry has been opened to determine the circumstances of the shooting.
The Somali government is defended by the African Union's 22,000-strong AMISOM mission against the AL-Qaeda-linked Shebab group, which has vowed to overthrow the country's fragile Western-backed authorities.
Confronted with AMISOM's superior fire power, Shebab militants were chased out of Mogadishu in August 2011.
After a relative calm in the Somali capital, the Shebab have ramped up attacks in recent months, taking advantage of the apathy of the AMISOM mission and the weakness of Somalia's central government.
AMISOM's effectiveness is hampered by mutual suspicion and jealousy among the main troop contributing countries and a lack of coordination, funds and focus.
It is also struggling to adapt to a rural counter-insurgency as Shebab fighters increasingly shift their battle from cities to the countryside.