A member of the US-backed Syrian Democratic Forces (SDF), made up of an alliance of Arab and Kurdish fighters, removes an Islamic State group flag in the town of Tabqa, about 55 kilometres (35 miles) west of Raqa city, on April 30, 2017, as they advance in their battle for the group's de facto capital. - US-backed fighters have captured 80 percent of Syria's Tabqa from the Islamic State group, a monitor said on May 1, a week after they first entered the town. (Photo by DELIL SOULEIMAN / AFP)        (Photo credit should read DELIL SOULEIMAN/AFP/Getty Images)