Iraq's Popular Mobilization Units (PMU) has had the city of Tal Afar surrounded for months, awaiting approval to launch a siege against the Islamic State (IS). That approval, however, might never come for the controversial group.
Some officials are worried about what might happen if the largely Shiite PMU leads the liberation of the predominately Sunni Arab and Turkmen city, which has been under IS control since June 2014. There are different theories as to why no action has been taken yet.