Serious irregularities have been reported by independent observers monitoring Ukraine’s presidential election.It follows a tense campaign overshadowed by claims of dirty tricks. Prime Minister Viktor Yanukovych is hoping to trade places for the top job. He is backed by the political establishment and much of Ukraine’s business elite. Hoping to stand in his way is Viktor Yushchenko, a Western-leaning liberal. He has alleged an elaborate plan has been hatched to rig the election and, amid claims of an assassination attempt, he says he was deliberately poisoned. The authorities deny any involvement. Yushchenko also denounces outgoing President Leonid Kuchma and his ministers as ‘criminals’, claiming they have plundered Ukraine. The vote is tantamount to a referendum on Kuchma’s rule as he is backing his prime minister. Pre-election polls showed Yushchenko and Yanukovych are neck and neck. Turnout in the capital Kiev was reported to be high after a spirted campaign that caught the public interest. The European Union and the United States have called for a fair contest But reports from the observers put that prospect in doubt. With security forces fearing protests, barriers have been erected around the Election Commission building, where days ago up to 100,000 people rallied, demanding an honest poll. Ukrainian troops and police are also out in force.