Fighters battling Islamic State gather trove of documents

By Idrees Ali and Yeganeh Torbati WASHINGTON (Reuters) - U.S.-backed forces fighting to drive Islamic State out of northern Syria have gathered a massive trove of documents and data belonging to the militant group, potentially shedding more light on its operations, a U.S. military official said on Wednesday. The material, gathered as fighters moved from village to village surrounding the town of Manbij, includes notebooks, laptops, USB drives, and even advanced math and science textbooks rewritt