BEIRUT (AFP) – The top US envoy to the Middle East called for the “complete and immediate” withdrawal of Syrian troops from Lebanon and demanded an investigation into the assassination of former prime minister Rafiq Hariri. “Mr Hariri’s death should give renewed impetus to achieving a free, independent and sovereign Lebanon,” Assistant Secretary of State for Near Eastern Affairs William Burns told reporters. “What that means is the immediate and complete implementation of UN Security Council Resolution 1559, and what that means is the complete and immediate withdrawal by Syria,” he said after talks with Foreign Minister Mahmud Hammud.