LA PAZ, BOLIVIA (NYTIMES) - President Evo Morales of Bolivia on Wednesday (Oct 23) claimed that he won Sunday's election by a margin wide enough to avoid a runoff, escalating a dispute over a vote marred by allegations of irregularities and by violent clashes.

Mr Morales, who has been in office since 2006, asserted that he would declare a "state of emergency" to fight back against what he characterised as a foreign-backed coup attempt.

"I want the world to know that until now we have stood by patiently to avoid violence," he said during a news conference in La Paz, the seat of the presidency.

The outcome of the vote has been in dispute since election officials released preliminary results on Sunday night that pointed to a runoff between Mr Morales and Mr Carlos Mesa, a former president - only to backtrack within 24 hours.

On Monday night, election officials released an updated vote tally showing that Mr Morales was leading by more than 10 percentage points, the margin required to avoid a runoff.

The announcement provoked a wave of huge demonstrations and attacks on election facilities on Monday night. Protesters took to the streets again on Tuesday night in La Paz and other cities.

Many chanted, "Fraud, fraud, fraud!"

Election observers from the Organisation of American States, which deployed a large mission to monitor the vote, issued a withering assessment of the integrity on the process on Monday night.

The mission said that the trend reversal between Sunday and Monday was at odds with independent tallies of the results and asserted that the outcome warranted a second round.

As of Wednesday morning, with nearly 97 per cent of the ballots counted, the latest official count showed Mr Morales with 46.5 per cent of the vote, about 9.5 points ahead of Mr Mesa.

Union leaders and activists called for a strike on Wednesday to protest what they regard as Mr Morales' attempt to steal the election.

The legitimacy of Mr Morales' mere candidacy was in dispute well before the vote.

The President in 2016 convened a referendum seeking to do away with term limits. Voters narrowly rejected that effort.

But a year later, the country's constitutional court ruled that term limits violated an international human rights treaty from the 1960s, a decision questioned by many experts.

As of Wednesday morning, the Supreme Electoral Tribunal had not issued a final comprehensive count of the vote.

Concerns about the fairness of the process grew when Mr Antonio Costas, a vice-president on the tribunal, resigned in protest over his colleague's decision to stop issuing periodic vote tally updates on Monday, breaking with what had been the norm in previous elections.

A few hours before his resignation was announced, Mr Costas said in an interview on Tuesday that he had no reason to believe fraud had been committed.

The President's rival, Mr Mesa, has called for mobilisations across the country, saying he fears that Morales loyalists could be working to rig the vote behind the scenes.

"It's clear there is a gigantic fraud in the works," said Mr Mesa. "We will be permanently mobilised, and I will stand with you, until there is recognition that the second round must take place because it is legitimately the vote of the Bolivian people."

Bolivians are bracing for growing violence and unrest as the dispute goes on.

Ms Judith Contreras, 57, a currency trader in downtown La Paz, watched on Tuesday as security forces barricading a road to the presidential compound held back a group of protesters by lobbing tear gas canisters.

"I fear there could be a war," she said. "They're going to have to oust him by force."

Ms Contreras said she voted for Mr Morales and had high hopes for him when he was first elected in 2005.

"The hope was that since he was a humble person, we all felt he would do good things," she said.

But in recent years, Ms Contreras said, she has come to distrust many of the people Mr Morales surrounded himself with, seeing them as greedy, corrupt and authoritarian.

"We're essentially stumbling into a democracy," she said. "They're not making our votes count, and that is the most painful thing."

Mr Abel Peredo Guerrero, 27, a medical resident who is training to become a surgeon, said many young Bolivians believed that the economy was showing signs of strain - and that Mr Morales had squandered money on questionable projects, like a new 29-story presidential compound, which he travels to by helicopter.

"Most professionals want to leave the country," Mr Peredo said, noting that his US$580 (S$789.58) monthly salary makes it hard to make ends meet.

"This country needs a change, and that change will only come with a new government."

He said he had been feeling a mix of hope and fear since Sunday, as critics of Mr Morales took to the streets in large numbers.

"All throughout the country, a spark has been lit for democracy," he said.

But bloodshed, he said, seems likely: "The consequences are very serious."