Ouagadougou - Roch Marc Christian Kabore has won Burkina Faso's presidential election, official results showed, after a year of turmoil that saw the west African country's former leader deposed and the military try to seize power.Kabore, who governed under former strongman Blaise Compaore before turning his back on the old regime, won the vote in the first round with 53.49% of ballots, the electoral commission said late on Monday."We must get to work immediately. Together we must serve the country," he told a crowd of several thousand supporters outside his party headquarters, pledging his "determination to open up the opportunities for a better tomorrow".Kabore's main rival Zephirin Diabre, who took 29.65% of votes, congratulated the former premier just before the results were released, according to an AFP journalist at the scene.Year of upheavalThe new president also expressed his "warm congratulations" to the election authorities that organised the poll, the first time in almost three decades Burkina has voted in a new leader.The poll caps more than a year of upheaval in the country after Compaore was ousted in October 2014 by a popular uprising, after trying to change the constitution to extend his 27-year rule.The country was once again plunged into turmoil in September when the elite presidential guard loyal to the former strongman tried to seize power, forcing the elections to be delayed.Finally held on November 29, the poll went off largely without incident, though some ballot stations were forced to stay open later than scheduled after long queues formed outside.'Rupture with the old'People in Burkina, a poor nation of 18 million people with a history of coups, are hoping the election will usher in a long era of peaceful democracy.Kabore, a former banker seen as a consensus figure by some and an opportunist by others, has pledged to build "a new Burkina Faso" by fighting youth unemployment, improving education and modernising the health system."We have had a total rupture with the old system," Kabore said Sunday, pledging to "bring real change to the country".For over a decade he led the ruling Congress for Democracy and Progress (CDP) party and was seen as Compaore's likely heir, but fell out with the strongman in 2012 and last year formed his own opposition party.The 58-year-old managed to garner a broad coalition of support from Campore supporters and opponents, as well as from cities and rural areas.Michel Kafando, who has presided over the transitional regime put in place after Compaore fled, praised the vote as "a victory... for the Burkinabe people".It was "the first fully democratic, transparent" election since 1978, when the former French colony was still known as Upper Volta, Kafando said.'Sighing with relief'Turnout was strong in all of the country's 45 provinces, said head of the electoral commission CENI, Barthelemy Kere, praising the "patience, tolerance and understanding" of the 5.5 million-strong electorate.Observers said turnout in the polls, where voters also elected members of a new parliament, was certainly higher than during elections during the Compaore era."We're smiling broadly, we're sighing with relief," said Halidou Ouedraogo, chairman of CODEL, the civil society platform monitoring the election."The Burkinabe people rose to the challenge of holding these historic elections in a calmer atmosphere."UN Secretary-General Ban Ki-moon cheered the "peaceful atmosphere" in which the election was conducted, as well as the "strong participation of women in the electoral process," his spokesperson Stephane Dujarric said.