A senior Iraqi official has said the government is incapable of managing prisons, hours after an attempted jail break left at least nine people dead.
At least nine people were killed in the prison escape bid near Baghdad
Deputy Justice Minister for Prisons Bhushu Ibrahim Ali said the authorities lacked the technical and financial capacities needed to supervise prisons.
The failed Baghdad escape bid was the result of negligence, he told the BBC.
He accused the government of asking the US to hand over control of Iraqi jails for domestic political purposes.
The shootings in Baghdad come only days after the US said it would not hand over detainees to the Iraqi authorities until they raised levels of care in prison facilities.
The US military said four wardens, four prisoners and an interpreter died in a jail at the Adala military base in Kadhimiya, but there are reports of up to 20 deaths.
Five prisoners and a US soldier were wounded, the US military added.
The inmates - described as suspected insurgents - were being transferred within the base when shooting began.
Brig-Gen Jalil Khalaf, commander of the Adala base, said the incident had not been an uprising, but an unsuccessful escape attempt.
"The prison now is calm, and the investigation is ongoing," he told Reuters news agency.
All prisoners have been accounted for, officials said.
Adala base, said to hold between 90 and 200 inmates, is a joint Iraqi police and army compound next to the River Tigris.
After the war it was used by the US military and called Camp Justice.
On Sunday, an official said Iraq had to meet US standards after the discovery of 170 detainees at an interior ministry centre, some allegedly suffering from abuse and starvation.
The alleged abuse discovered by US and Iraqi troops included electric shocks and the removal of finger nails.
Prison conditions in Iraq became a matter of controversy in the months after the 2003 invasion that overthrew Saddam Hussein, beginning with abuse scandals involving US military guards.
Sunni Arabs say the latest alleged abuse was perpetrated by Shia sectarian militias who they say had been given control of interior ministry prisoners.