'A threat from within': Iraq and the rise of its militias

Shaped by the fight against Isis and a fateful US drone strike, the factions now pose a danger to Baghdad's weak government

The dust had barely settled on the fall of Iraq's second city when the call came. It was June 2014 and Islamic State had just captured Mosul, the prize in a fight for control of a country already scarred by more than a decade of war.

Just four days after the city's capture, Grand Ayatollah Ali al-Sistani, the most revered Shia cleric in Iraq, issued a fatwa urging Iraqis to volunteer in the fight against the militants. Tens of thousands of mostly young men from the poor Shia south and Baghdad suburbs flocked to recruiting centres, military camps and militia headquarters.