HARARE - President Robert Mugabe was dismissed as leader of Zimbabwe's ruling ZANU-PF party on Sunday in a move to force a peaceful end to his 37 years in power following a de facto military coup.He was replaced by Emmerson Mnangagwa, the deputy he sacked this month, sources at a special ZANU-PF meeting to decide Mugabe's fate told Reuters."He has been expelled," one of the delegates said. "Mnangagwa is our new leader."Mugabe's wife Grace, who had harbored ambitions of succeeding Mugabe, was also expelled from the party.Speaking before the meeting, war veterans' leader Chris Mutsvangwa said the 93-year-old Mugabe was running out of time to negotiate his departure and should leave the country while he could."He's trying to bargain for a dignified exit," he said.Mutsvangwa followed up with threats to call for street protests if Mugabe refused to go, telling reporters: "We will bring back the crowds and they will do their business."Mnangagwa, a former state security chief known as "The Crocodile," is now in line to head an interim post-Mugabe unity government that will focus on rebuilding ties with the outside world and stabilizing an economy in freefall.On Saturday, hundreds of thousands of people flooded the streets of Harare, singing, dancing and hugging soldiers in an outpouring of elation at Mugabe's expected overthrow.His stunning downfall in just four days is likely to send shockwaves across Africa, where a number of entrenched strongmen, from Uganda's Yoweri Museveni to Democratic Republic of Congo's Joseph Kabila, are facing mounting pressure to quit.SUPPORT EVAPORATINGMen, women and children ran alongside the armored cars and troops who stepped in this week to oust the man who has ruled since independence from Britain in 1980.Under house arrest in his lavish "Blue Roof" compound, Mugabe has refused to stand down even as he has watched his support from party, security services and people evaporate in less than three days.His nephew, Patrick Zhuwao, told Reuters that Mugabe and his wife were "ready to die for what is correct" rather than step down in order to legitimize what he described as a coup.But on Harare's streets, few seemed to care about the legal niceties as they heralded a "second liberation" for the former British colony and spoke of their dreams for political and economic change after two decades of deepening repression and hardship."These are tears of joy," said Frank Mutsindikwa, 34, holding aloft the Zimbabwean flag. "I've been waiting all my life for this day. Free at last. We are free at last."The huge crowds in Harare have given a quasi-democratic veneer to the army's intervention, backing its assertion that it is merely effecting a constitutional transfer of power, rather than a plain coup, which would entail a diplomatic backlash.Despite the euphoria, some Mugabe opponents are uneasy about the prominent role played by the military, and fear Zimbabwe might be swapping one army-backed autocrat with another, rather than allowing the people to choose their next leader."The real danger of the current situation is that having got their new preferred candidate into State House, the military will want to keep him or her there, no matter what the electorate wills," former education minister David Coltart said.The United States, a long-time Mugabe critic, said it was looking forward to a new era in Zimbabwe, while President Ian Khama of neighboring Botswana said Mugabe had no diplomatic support in the region and should resign at once.