BUJUMBURA (Reuters) - Burundi President Pierre Nkurunziza won a third term in office on Friday after the opposition boycotted the vote, a victory that leaves the east African nation politically divided and facing international isolation after months of unrest.
Nkurunziza's decision to seek a third term plunged Burundi into its biggest crisis since an ethnically charged civil war ended in 2005. The opposition says Nkurunziza's bid violated the constitution and could spark another conflict.
Major donors United States and the European Union, both critical of Nkurunziza, have threatened measures from cutting aid to imposing sanctions after Burundi went ahead with an election they said could not be free or fair.
Nkurunziza won 69.41 percent of the 2.8 million votes cast on Tuesday, winning handsomely in the rural regions where most of Burundi's 10 million people live, the national electoral commission chief announced at a press conference on Friday.
His nearest rival, Agathon Rwasa, took 18.99 percent.
The opposition, which had complained about frequent police intimidation of its members and shuttering of private media, rejected the result.
"We will not recognize the outcome of this election and the institutions resulting from it," Frederic Bamvuginyumvira, president of the opposition FRODEBU party, said after Nkurunziza was announced the winner.
The presidency was not immediately available for comment but has in the past rejected claims of police heavy-handedness. Nkurunziza's supporters also point to a constitutional court ruling allowing the president to seek a third term.
Extremely low turnout in Bujumbura, where weeks of protests against Nkurunziza's presidency took place in the run-up to the vote, indicate opposition to Nkurunziza's presidency remains strong. Turnout in the capital stood at 29.75 percent against a national average of 73.44 percent.
African leaders and Western powers had called for the delay of the July 21 vote due to growing insecurity. Dozens were killed during weeks of pre-election demonstrations, a failed coup and clashes between rebel soldiers and the army.
Few had expected Nkurunziza to lose. The names of rival candidates were printed on ballot papers, but the opposition boycotted the race and called for voters to do the same.
Earlier this week Rwasa, leader of the opposition Amizero y'Abarundi coalition, said a unity government should be formed immediately to stop Burundi slipping into conflict. He also called for a new election within a year.
A presidential adviser said on Wednesday a unity government would not be opposed. But he rejected as "impossible" the idea of cutting short any new mandate.
Regional African leaders and Western diplomats fear Burundi could tumble back into civil war if tensions are not resolved. That is a frightening prospect for a region scarred by the 1994 genocide in neighboring Rwanda, where about 800,000 Tutsis and moderate Hutus were killed. Burundi has a similar ethnic makeup.
Washington and Brussels both warned the poll would not be credible, admonishing Nkurunziza for breaking the two-term limit agreed in a key peace deal that ended the 12-year civil war and kept ethnic tensions in check.
More then 175,000 people have fled to neighboring countries to seek refuge and the United Nations has warned that more than half a million Burundians may end up leaving the country if the crisis persists.
Writing by Drazen Jorgic; Editing by Mark Heinrich