Eyes in the sky: Inside the hunt for Islamic State fighters in Syria

Militants firing from bombed-out buildings had ambushed a U.S.-backed militia on a rubble-strewn street in Raqqah, Islamic State's self-declared capital and one of its last urban strongholds. The militia was pinned down and their commander wanted the drone to take out the gunmen. The pilot studied the surveillance video streaming onto his screen. A captain, he instructed the staff sergeant at his side to set the drone's target sights and powered up a Hellfire missile under its wing. "Rifle," the pilot said and the missile soared away.