Zimbabweans have begun voting in an election billed as the most important in the troubled country's history.Millions of voters in the southern African state are poised to decide whether to end controversial president Robert Mugabe's 28-year reign.Security forces have been put on full alert to quash any violence, with soldiers patrolling the streets of the capital Harare.Mr Mugabe, who has been accused of stealing three elections since 2000, must win more than half the presidential vote to avoid a second poll that could see his opponents unite on the same ticket.His opponents have joined together to accuse the 84-year-old of planning to rig the poll in a desperate bid to cling to power.He has given away hundreds of cars to doctors and handed out farm equipment and public buses in what critics say is an attempt to buy votes.But the Zimbabwe Electoral Commission rejected opposition accusations that the electoral roll is padded with tens of thousands of "ghost voters" to ensure a victory for the ruling ZANU-PF party.Mr Mugabe blames the West for the collapse of the economy in his once-prosperous nation, now suffering the world's highest inflation at 100,000 percent, as well as food and fuel shortages.Britain and other countries imposed sanctions after he began seizing white-owned farms to give to landless blacks.Opponents blame the former guerrilla leader's policies for ruining Zimbabwe and say he has resorted to violence and intimidation to silence critics.In one of his last rallies before Saturday's poll, Mr Mugabe mocked the opposition Movement for Democratic Change (MDC) and attacked former colonial power Britain."This is a vote against the British. The fight is not against the MDC - the MDC is just a puppet, a mouthpiece of the British," he said.© Independent Television News Limited 2008. All rights reserved.