At least 10 people have been killed in a shoot-out between jailed Islamist militants and security officers at a prison in Somalia, government spokesman Ismail Mukhtar has said.
The al-Shabab militants had attempted to escape from the heavily guarded prison in the capital, Mogadishu.
As at press time, investigations were ongoing to ascertain how the militants obtained weapons.
Some reports however suggested that an inmate managed to disarm a warden and then a group of them raided the armoury.
The BBC’s Bella Sheegow in Mogadishu says Monday’s incident is highly embarrassing for the government as the prison, the second biggest in Somalia, is guarded by elite forces.
The most dangerous al-Shabab militants are kept in the prison, including those serving life sentences or awaiting execution after being sentenced to death.
Somali troops have been battling to curb the insurgency
“We will not leave anything to chance. The government is investigating how this happened and who was responsible for what happened as well as who facilitated the inmates to get the weapons,” Acting Justice Minister Hassan Hussein Haji said.
Mr Mukhtar said none of the prisoners had managed to escape.
He said four militants were killed in the shoot-out.
He did not give details on who the other six were, except to say that the prison guards had also suffered casualties.
Al-Shabab, which is linked to al-Qaeda, has been waging a brutal insurgency in Somalia for more than a decade.