Final results from Peru's presidential election -- in which leftist Pedro Castillo considers himself the winner -- are still days away, officials said Thursday, as a prosecutor sought preventive custody for corruption-accused candidate Keiko Fujimori.

Right-wing populist Fujimori, daughter of a scandal-tainted former Peruvian president, is disputing thousands of votes cast four days earlier as she trails in the nail-biting final count.

Country profile of Peru, where a presidential runoff vote was held on June 6 Country profile of Peru, where a presidential runoff vote was held on June 6 Photo: AFP / Gustavo IZUS

Fujimori's corruption trial would be delayed if she wins her presidential race against Castillo, who is clinging to a narrow lead.

Prosecutors have said they would seek a jail term on charges of taking money from scandal-tainted Brazilian construction giant Odebrecht to fund failed presidential bids in 2011 and 2016.

The 46-year-old denies the allegations, but has already spent 16 months in pre-trial detention.

Rural school teacher Pedro Castillo has cast himself as the winner of Peru's presidential elections Rural school teacher Pedro Castillo has cast himself as the winner of Peru's presidential elections Photo: AFP / Gian MASKO

Late Wednesday Fujimori, who has claimed electoral fraud, asked Peru's National Electoral Tribunal (JNE) to annul the results from more than 800 polling stations, the equivalent of 200,000 votes. The tribunal is expected to take about 10 days to weigh the request.

Fujimori has also asked for another 300,000 ballots to be reviewed.

Right-wing candidate Keiko Fujimori wants 200,000 votes in Peru's presidential election to be thrown out, and another 300,000 to be reviewed Right-wing candidate Keiko Fujimori wants 200,000 votes in Peru's presidential election to be thrown out, and another 300,000 to be reviewed Photo: AFP / Luka GONZALES

If the JNE rules in Fujimori's favor, it could shift the balance.

Rural school teacher and trade unionist Castillo was leading by about 70,000 votes with over 99 percent of the tally completed by Thursday.

Rural supporters of Pedro Castillo march outside Peru's national election office in a show of support for their presidential candidate Rural supporters of Pedro Castillo march outside Peru's national election office in a show of support for their presidential candidate Photo: AFP / ERNESTO BENAVIDES

According to the ONPE electoral body, Castillo had 50.18 percent of the vote compared to 49.81 percent for Fujimori in her third presidential race.

Under Peruvian law, Fujimori was allowed to contest the election as she had not been convicted of a crime.

Supporters of Pedro Castillo in traditional regional Andean garb marched in downtown Lima to show support for the leftist candidate Supporters of Pedro Castillo in traditional regional Andean garb marched in downtown Lima to show support for the leftist candidate Photo: AFP / ERNESTO BENAVIDES

On Thursday, prosecutor Jose Domingo Perez asked an organized crime court to take Fujimori into custody for allegedly having met with a witness in the case, violating the conditions of her parole.

The witness, Miguel Angel Torres, had accompanied Fujimori to a press conference on Wednesday.

"There is no fear that this preventive detention will take place," Fujimori said in reaction to the prosecutor's request.

Rural supporters of Pedro Castillo march outside Peru's national election office in a show of support for their presidential candidate Rural supporters of Pedro Castillo march outside Peru's national election office in a show of support for their presidential candidate Photo: AFP / ERNESTO BENAVIDES

She claimed Perez was attempting "to distract us, unsettle us."

Peruvians voted on Sunday for their fifth president in three years after a series of crises and corruption scandals saw three different leaders in office in a single week last year.

Despite there being no official result, Argentina's President Alberto Fernandez on Thursday became the first sitting leader to congratulate Castillo as Peru's "president-elect."

The center-left leader said on Twitter he had contacted Castillo and "expressed my wish that we join forces in favor of Latin America."

Bolivia's former leftist president Evo Morales sent a message of congratulations, while Brazil's ex-leader Luis Inacio Lula da Silva celebrated Castillo's "victory" on Twitter and said the result "represents another advance for the popular struggle in our beloved Latin America."

But Brazil's incumbent leader, far-right Jair Bolsonaro, lamented the possible leftist victory, telling an evangelical event that a "miracle" was needed to stop it.

As tension grew, Castillo supporters rallied late Wednesday outside the vote counting office in Lima, while a pro-Fujimori crowd gathered in a park in the capital to denounce vote "fraud."

Peruvian authorities and election observers have dismissed any possibility of vote-counting fraud.

As in Peru's three previous presidential elections, the tail-end of vote counting has been slow due to delays in the arrival of ballots in Lima from rural and jungle areas, and from abroad -- where one million of the country's 25 million eligible voters live.

Fujimori has taken most of the expat votes, but Castillo is popular among rural electors.

Whoever wins will lead a nation battered by recession and the world's highest coronavirus death rate, with more than 187,000 deaths among its 33 million population.

Two million Peruvians lost their jobs during the pandemic and nearly a third now live in poverty, official figures show.

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