Lebanese opposition leaders yesterday accused Syria and its local allies of trying to block elections due in May to stave off likely defeat and prolong the life of the mainly pro-Syrian Parliament. As Syrian forces evacuated positions near their main military and intelligence headquarters in Lebanon yesterday after a night of bomb scares in Beirut, opposition leaders had been meeting to discuss a protracted government crisis. "The Lebanese-Syrian security authority, with its political and constitutional symbols, is working to sabotage the parliamentary polls in a dangerous attempt to extend the term of the current Parliament, illegally and unconstitutionally," the loosely allied opposition front said in a statement.The statement reiterated an opposition demand for a government composed of ministers not running in the polls. "Everyone should bear their historic responsibilities and hold the elections without hindrance or delay," it said. Syrian-backed Prime Minister-designate Omar Karami has said he will step down today because he had failed to convince the opposition to join a national unity Cabinet. Meanwhile, witnesses said troops had dismantled two military posts near Anjar, the nerve center of Syria's presence in Lebanon. About 18 trucks loaded with soldiers and equipment from the posts near the village in the Bekaa Valley drove into Syria overnight. Troops in the southern Bekaa were also seen preparing to abandon their posts.