Violence broke out in several Bolivian cities Monday after the main opposition candidate rejected presidential election results that seemed set to give victory to long-time incumbent Evo Morales, as international monitors voiced "deep concern."
Rival supporters clashed in the capital La Paz, while in the southern city of Sucre an angry mob set a local electoral authority's headquarters on fire, TV images showed.
Protesters clashed with police in the mining city of Potosi and attacked the local electoral authority as well as local government offices.
Riot-police dispersed a crowd who tried to storm the electoral offices in the Andean city of Oruro, south of La Paz.
Clashes were also reported in Tarija in the south, Cochabamba in the center and Cobija in the north.
Carlos Mesa, who came a close second to Morales in Sunday's polls -- forcing a run-off, according to preliminary results -- denounced revised results released by election authorities as a "fraud."
"We are not going to recognize those results that are part of a shameful, consumated fraud, that is putting Bolivian society in a situation of unnecessary tension," said Mesa.
Mesa, a former president of the country between 2001-2005, accused Morales of colluding with the Supreme Electoral Tribunal (TSE) to tweak delayed results and avoid a run-off.
The United States' top diplomat for Latin America said the Electoral Tribunal was attempting "to subvert Bolivia's democracy by delaying the vote count and taking actions that undermine the credibility of Bolivia's elections."
"We call on the TSE to immediately act to restore credibility in the vote counting process," the official, Michael Kozak, said on Twitter.
Election monitors from the Organization of American States voiced "deep concern" at sudden changes to the election count to show Morales closing in on an outright victory in the first round.
The OAS observer mission in the country expressed "surprise at the drastic and hard-to-explain change in the trend of the preliminary results revealed after the closing of the polls," it said in a statement.
Preliminary results released late Sunday showed neither Morales, 59, nor 66-year-old Mesa with a majority and "clearly indicated a second round," the OAS mission said.
The partial results put Morales in the lead with 45 percent of the votes, with Mesa on 38 percent, meaning Morales would have to contest a run-off for the first time.
But results released late Monday, after a long delay, showed Morales edging towards an outright victory with 95 percent of the votes counted.
The OAS called on the election authority to "firmly defend the will of the Bolivian people" and called for calm on the streets.
"It is extremely important that calm is maintained and any form of violence is avoided in this delicate situation," it added.
Count center protests
Morales, Latin America's longest-serving president, is controversially seeking a fourth term.
He obtained Constitutional Court permission in 2017 to run again for president even though the constitution allows only two consecutive terms.
The former coca farmer and leftist union leader has led the poor but resource-rich Latin American country for the past 13 years, though his popularity has waned amid allegations of corruption and authoritarianism.
He has led the country since taking office in 2006, when he became its first indigenous president.
A new mandate would keep him in power until 2025.
As leader of his Movement for Socialism Party (MAS), Morales points to a decade of economic stability and considerable industrialization as his achievements, while insisting he has brought "dignity" to Bolivia's indigenous population, the largest in Latin America.
He has come under severe criticism this year as wildfires in August and September ravaged Bolivia's forests and grasslands, with activists saying his policies encouraged the use of blazes to clear farmland.