Scores of prisoners have been killed during a jail break organised by the Islamic State of Iraq and the Levant armed group in eastern Iraq, in which 40 inmates managed to escape, officials have said.
Police officials said on Saturday that at least 50 inmates and 12 police officers were killed at the Al-Khalis prison during a riot.
There were conflicting accounts over the cause of the incident in the Diyala province.
In a statement carried on pro-ISIL websites, the local chapter of the armed group claimed a completely different account of the incident, describing it as a coordinated operation involving the use of multiple explosives outside the prison. The statement claimed that 30 ISIL members were among those who escaped.
Oudi al-Khadran, mayor of the town where the prison is located, and Colonel Ahmed al-Timimi, of the Diyala province security operations centre, confirmed that ISIL caused the jail break, the Reuters news agency reported.
However, Iraqi military official Brigadier General Saad Maan Ibrahim told the Associated Press news agency that a fight broke out among the inmates of Khalis prison and when guards went to investigate, they were overpowered and had their weapons taken.
Ibrahim said security forces were cordoning off the area and hunting for the escaped inmates, some of whom were wanted on terrorism charges.
Jail breaks are common in Iraq and usually a result of assaults from armed groups seeking to free their comrades in prison.
The most stunning one was in mid-2013, when Iraq's infamous Abu Ghraib prison was attacked with mortar shells and suicide bombers, freeing more than 500 inmates.
The violence happened as a series of suicide attacks targeting Shia places of worship also in Diyala province killed at least 22 people.