It was supposed to be a routine job, police say. Move 69 prisoners from an outlying town to a jail in southern Baghdad. But before they arrived at their destination, every single prisoner had been killed. But mystery surrounds the massacre. According to some sources, it’s likely that they were killed to prevent them joining the rebellion. The official account, though, given hours after the killing on Monday by the governor of Hillah, 92km (57 miles) south of Baghdad, was that militants had attacked the convoy killing 10 prisoners and one policeman in the crossfire. Scroll down for video Shiite volunteers, who have joined the Iraqi army to fight against the predominantly Sunni militants from the radical Islamic State of Iraq and the Levant (ISIS), demonstrate their skills during a graduation ceremony after completing their field training in Najaf
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Mystery surrounds the massacre with several accounts of the incident
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'Prisoners died when extremists attacked their transfer convoy' - officials
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Anonymous police sources say they were killed to prevent them joining Isis
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Other sources say an attack was staged before the prisoners were shot
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The prisoners were being transferred to a jail in southern Baghdad
A year ago @placeholder launched its biggest military operation in years, attacking two jails.