Video report by ITV News correspondent Emma Murphy
Al Qaeda claimed has responsibility for simultaneous raids on two Iraqi prisons and said more than 500 inmates had been set free in the operation.
The Islamic State of Iraq and the Levant, a group formed earlier this year through a merger of al Qaeda's affiliates in Syria and Iraq, said it had stormed Baghdad's Abu Ghraib jail and another, some 12 miles north of the capital, after months of preparation.
Monday's attacks came exactly a year after the leader of al Qaeda's Iraqi branch, Abu Bakr al-Baghdadi, launched a "Breaking the Walls" campaign that made freeing its imprisoned members a top priority, the group said in a statement.
Sunni Islamist militants have in recent months been regaining momentum in their insurgency against Iraq's Shi'ite-led government, which came to power after the US invasion to oust Saddam Hussein.