AMMAN (Reuters) - U.S-backed Syrian Democratic Forces said they expelled had Syrian troops that briefly took control of a string of villages in oil rich areas east of the Euphrates river near the Iraqi border on Sunday. SDF forces led by the Kurdish YPG militia said they had waged a counter-attack against Syrian troops it said were backed by Russian forces, adding they were driven “far away” from four villages they had seized earlier in the day. “Our forces regained the initiative,” they said in a statement.