This breach on the notorious Abu Ghraib jail comes as sectarian violence brews while Sunni Muslim militants are gaining ground in their insurgency against the Shia-led government.
Here's what you need know.
1. 25 Were Killed, Several More Injured
Suicide bombers with explosives drove up to the gate of the prisons and blasted their way through the compound. Gunmen attacked guards with grenades and mortars. Ten policemen and four militants were killed in clashes in Abu Ghraib jail while 15 more were killed in a simultaneous attack on another prison, in Taji, around 12 miles north of Baghdad.
2. 500 Inmates Escaped
Hundreds of inmates fled from Abu Ghraib jail as insurgents attacked the high-security prison. The deadly attack was carried out by nine suicide bombers, 100 mortar shells, rocket propelled grenades as well as other intermediate and light weapons. Militants launched a similar strike on a prison in Taji, but guards managed to prevent any inmates escaping.
3. Senior Members of Al-Qaida on Death Row Are Loose
"The number of escaped inmates has reached 500, most of them were convicted senior members of al-Qaida and had received death sentences," Hakim al-Zamili, a senior member of the security and defence committee in parliament, told Reuters. Relations between Islam's two main denominations have been put under further strain from the civil war in Syria, which has drawn in Shia and Sunni fighters from Iraq and beyond to fight against each other.
4.This is the Same Jail Made Notorious By Photographs Showing US Soldier Abuse
US handed over control of the jail to Iraqi forces in 2011. The prison made notorious a decade ago by photographs showing abuse and torture of prisoners by US soldiers.
5. Tensions Between Sunnis and Shia Muslims Are Growing
Two years have passed since US troops withdrew from Iraq. Now, it appears that the crisis oil rich country is no longer the presence of foreign troop, but the division of its people. Sunni insurgents, including the al-Qaida-affiliated Islamic State of Iraq, have been regaining strength in recent months and striking on an almost daily basis against Shia Muslims and security forces amongst other targets.
Recent attacks have targeted public places such as mosques, amateur football matches, shopping areas and cafes where people gather to socialise after breaking their daily fast for the holy Muslim month of Ramadan.