As militants seize control of Iraq's northern city Mosul, the residents take refuge in Baghdad and settle in makeshift homes. The fall of Mosul, a largely Sunni Arab city, after years of ethnic and sectarian fighting, deals a serious blow to the government’s efforts to fight militants who have regained ground and momentum in Iraq over the past year, taking Falluja and parts of Ramadi, west of Baghdad, at the start of the year.