Beirut (dpa) - A US-backed alliance of Syrian Kurdish and Arab forces were Saturday closing in on a strategic dam held by Islamic State in northern Syria, a monitoring group said. The Tishreen Dam is located about 22 kilometres from al-Raqqa, Islamic State's de-facto capital in Syria. It is one of three major dams on the Euphrates River that flows from Turkey through Syria and into Iraq, and supplies much of northern Syria with electricity. The Democratic Forces of Syria (DFS), a coalition comprising mainly local Kurds, Arabs and Assyrians, seized the eastern bank of the Euphrates close to Tishreen...