This frame grab from a video provided by the Syria Democratic Forces , shows fighters from the SDF opening fire on an Islamic State group’s position, in Raqqa’s eastern countryside, Syria, Monday, March 6, 2017. The main U.S.-backed force fighting the Islamic State group in Syria has enough fighters to capture the extremists’ de facto capital of Raqqa north of the country at a time when U.S. troops are playing a bigger role on the ground in the battle to conquer the city, a spokeswoman for the force said Friday, March 10, 2017.