Billionaire Petro Poroshenko declared victory Sunday in Ukraine 's presidential election , following preliminary exit polls that suggested he got 56 % of the vote . His closest challenger , former Ukrainian prime minister and leader of the Batkivshchyna party Yulia Tymoshenko , conceded the election after exit polls showed her with 13 % of the vote . Poroshenko , a candy tycoon known as the `` Chocolate King , '' is also a seasoned politician . The election took place Sunday despite a recent wave of deadly violence in the east and threats by pro-Russia separatists to prevent citizens from casting their ballots . Voters were picking a successor to ousted pro-Moscow President Viktor Yanukovych in a country torn apart by Russia 's takeover of Ukraine 's Crimea peninsula and bloody conflict with pro-Russia factions . The unrest has centered in the Donetsk and Luhansk regions , where separatists have claimed independence following a disputed referendum earlier this month -- and many there did not get to cast ballots Sunday . As of 3 p.m. ( 8 a.m . ET ) , some 528 polling sites out of 2,430 were open in the Donetsk region , the regional administration said . Local officials said there was 11.8 % turnout at these polling stations . Outside the country 's restive east , voting was progressing more normally . The Central Election Commission put voter turnout at nearly 38 % as of 3 p.m. local time , not including the Donetsk and Luhansk regions , Ukraine 's official Ukrinform news agency reported . In the city of Donetsk , the regional capital where pro-Russia militias are concentrated , there were no open polling stations , local officials said earlier . A CNN team driving through the city Sunday morning was not able to see a single polling station in operation . However , there were signs some voters were trying to go to polling stations in areas west and south of the city . Besides the presidential race , candidates are also running in municipal elections in some cities . The Organization for Security and Co-operation in Europe deployed 900 observers for the election -- the largest such mission in its history . Oleksandr Turchynov , Ukraine 's acting President , called the polls open and transparent . `` The voting was free , without artificial restrictions and administrative pressure , '' Turchynov said in a statement . U.S. President Barack Obama congratulated Ukrainians for casting their ballots Sunday and criticized Russian-backed separatists , whom he accused of trying to block voting . `` Despite provocations and violence , millions of Ukrainians went to the polls throughout the country , and even in parts of eastern Ukraine , where Russian-backed separatist groups sought to disenfranchise entire regions , some courageous Ukrainians still were able to cast their ballots , '' he said in a written statement . `` We commend the resolve of all those who participated , as well as the efforts of the Ukrainian government to conduct these elections in the face of those threats . '' Intimidation in eastern Ukraine appears widespread . Increasing violence in the east has led the authorities in Kiev to accuse Russia , which they say is backing the armed separatists , of seeking to disrupt the vote . Russia denies having direct influence over the militants , and Russian President Vladimir Putin has said he will respect the Ukrainians ' choice . Amid heightened tensions , instances of intimidation in eastern Ukraine appear widespread . A large separatist rally was held in a central Donetsk city square around lunchtime . The protesters , who chanted pro-Russia slogans as they were addressed by separatist leaders , were joined by a substantial number of militants on trucks , some firing guns into the air . On the back of some of the trucks were armed men who appeared to be Chechen . Two told a CNN team they were from the Chechen capital , Grozny , and one indicated that he was formerly a policemen in Chechnya and was in Donetsk to serve the Russian Federation . The men , who as Chechens are Russian citizens , said they were there as `` volunteers . '' But if their accounts were true , their presence in Donetsk would appear to indicate some kind of acquiescence by the Russian government at the least . Residents of Ukraine 's southeastern city of Mariupol saw new billboards on the streets Sunday urging them not to cast their ballots . The billboards were not at those locations the night before , residents said . Also in Mariupol , people talked on social media about being asked by local Russia supporters to boycott the election . The city is one of several where deadly clashes have erupted in recent weeks . The self-declared mayor of rebel stronghold Slovyansk , Vyacheslav Ponomaryov , has said that anyone who tries to vote there will be arrested . Also , an Italian journalist was killed Saturday near the flashpoint town , the Italian Foreign Ministry announced Sunday . The man , named as Andrea Rocchelli , was killed along with a Russian citizen , the ministry said . Reports suggested there had been mortar fire in the Slovyansk area . Ukraine 's 'Chocolate King ' aims for top job . Opinion : Free elections good for Ukraine , but could be bad for Putin . Putin 's 48 hours in St. Petersburg .
Obama accuses Russian-backed separatists of trying `` to disenfranchise entire regions '' including the eastern part of Ukraine where he is vacationing this week. Batkivshchyna party concedes defeat . Fewer than a quarter of polling stations were open in Donetsk region , officials say .