ALEPPO, SYRIA - FEBRUARY 10: Members of Free Syrian Army advance towards the center of al-Bab town of Aleppo during the 171th day of the 'Operation Euphrates Shield' in Aleppo, Syria on February 10, 2017. Operation Euphrates Shield, which involves Free Syrian Army fighters backed by Turkish forces, was launched last August to secure Turkeys border with Syria against terrorists and support opposition forces. Since November, the operation has focused on taking the town of Al-Bab, 30 kilometers (19 miles) south of the Turkish border, from Daesh. (Photo by Muhammed Nour/Anadolu Agency/Getty Images)