Bolivia's Supreme Electoral Tribunal (TSE) denied on Friday that irregularities had taken place in the vote count in order to help President Evo Morales win re-election and avoid a runoff.
The announcement by the TSE comes as opposition and pro-government protesters have clashed on the streets for three consecutive days, in the aftermath of a contested presidential election on October 20 where Morales emerged victorious.
The TSE referred critics to a report by the company Ethical Hacking, which had checked the electronic vote and did not find any kind of "alteration of the data."
But the company’s chief, Alvaro Andrade, said his firm did find "vulnerabilities" in the vote count, local media reported.
Carlos Mesa, who lost to President Morales in the election, has denounced the vote as fraudulent, insisting that results had been manipulated during a 24-hour period when the electoral count was suspended.
Since then, Bolivia has been consumed by weeks of protests and rioting by opposition supporters and supporters of Morales.
Three people have been killed and more than 300 injured in the ensuing violence.
Morales, a socialist who is Latin America's longest-serving president, has repeatedly dismissed opposition calls for him to step down.
On Friday several police forces also expressed their support for the opposition, referred to by Defense Minister Javier Zabaleta as a "defense mutiny."
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"The right says 'Evo has to resign.' I want to tell you, sisters and brothers, to all of Bolivia and the world, I will not resign," Morales said at a public event on Friday.
"We are elected by the people and we respect the constitution," he added.
Calls to end violence
The UN expressed its concerns about the situation on Thursday, urging both sides to restore "dialogue and peace."
"Nothing justifies clashes between Bolivians, and the death of citizens is unconceivable," the UN statement said in a statement that condemned "intolerance and violence."
An Organization of American States (OAS) delegation is in Bolivia carrying out an audit of the presidential vote.
The results of the audit will be released next week. But Mesa has said the terms of the audit were agreed upon "unilaterally" by Morales' government and the OAS, without any input from the opposition or other civil society groups.
jcg, ed/dr (AP, Reuters, dpa)