When ISIS fighters swept across Iraq in 2014, capturing major cities like Mosul, a humanitarian disaster on an unprecedented scale quickly unfolded. CNN looks at Iraq's bloody crisis up close:THE CRISIS IN NUMBERS ...Around a quarter of Iraq's population urgently require aid, according to the United Nations -- a situation that has accelerated in recent months as the struggle to remove ISIS from Iraqi territory intensifies. Photos: Iraqi forces push towards Mosul as refugees wait for aid Smoke rises from al-Qayyara in the late afternoon light, as ISIS burns crude oil to block visibility from above. Hide Caption 2 of 6 Photos: Iraqi forces push towards Mosul as refugees wait for aid Iraqi mother Piswa Treish holds a picture of her son (right) who was killed by ISIS. Hide Caption 6 of 6Tens of thousands of Iraqi civilians have lost their lives since 2003, though the number has spiked again under ISIS.

Source: CNN October 16, 2016 06:33 UTC