US-backed Kurdish and Arab fighters advance into the Islamic State (IS) jihadist's group bastion of Manbij, in northern Syria, on June 23, 2016. Backed by air strikes by the US-led coalition bombing IS in Syria and Iraq, fighters with the Syrian Democratic Forces (SDF) alliance entered Manbij from the south, a monitoring group said./ AFP / DELIL SOULEIMAN        (Photo credit should read DELIL SOULEIMAN/AFP/Getty Images)

Anti-ISIS Forces Recover Massive Collection of Documents in Syria

In a development that could provide significant insight into the workings of the Islamic State (ISIS), U.S.-backed forces fighting the extremist group in Syria have recovered a large collection of its documents and data.