Right-wing Flávio Bolsonaro has won the first round of Brazil's presidential election, beating left-wing President Lula da Silva, but falling short of an outright majority.
There will be a run-off between the two candidates on 25 October.
Bolsonaro is the son of the former president Jair Bolsonaro, who is serving a 27-year prison sentence for masterminding a failed coup after losing the 2022 election.
Sunday's vote was close, with President Lula polling slightly ahead during the campaign. With almost all of the votes counted, Bolsonaro has 47% to Lula's 45% of the vote.
Bolsonaro's result exceeded expectations, meaning the second round now looks like his to lose, given some of the other candidates knocked out in the first round were right-wing alternatives.
His Liberal Party (PL) also had the most governors, senators and federal deputies elected in the results so far, meaning the party is expected to have the most influence in Congress.
The majority of Latin America has now elected right-wing presidents, aligned to the Trump administration, and the run-off will determine whether Brazil – Latin America's largest country and economy – will follow suit.
After casting his ballot, Lula, 80, warned the choice was between democracy and "barbarism".
Bolsonaro, 45, said he wanted to "free the Brazilian people".
Lula and Bolsonaro are the two biggest names in Brazilian politics, on the left and right, and this campaign has polarised Brazil yet again: with themes of sovereignty, crime, the economy and corruption being top concerns for voters.
Lula is more popular in Brazil's poorer northeast, among low-income voters, Catholics, and women.
He is seeking a fourth term in office, after being elected in 2002, 2006 and then a later non-consecutive term in 2022. In that election, he beat Jair Bolsonaro by less than 2% of the vote, the closest presidential election result in Brazil's history.
After that election, Bolsonaro's supporters vandalised government buildings on 8 January 2023.
Jair Bolsonaro was banned from running for re-election even before his prison sentence, but endorsed his eldest son Flávio to run in his place. Jair Bolsonaro's wife, Michelle, was elected to the Senate on Sunday.
Flávio Bolsonaro has pledged to grant his father, and his supporters responsible for the 8 January riots, amnesty if elected.
He is more popular in the south, and among wealthier voters and evangelical Christians.
Bolsonaro said on Sunday he was "very happy" to have led Lula in the first-round vote, and expressed confidence that he would clinch a run-off victory in three weeks' time.
"I am very happy with the real possibility that, three weeks from now, Brazil will give a definitive answer by choosing a modern government," he said, according to AFP.
Lula said the outcome of the vote was "unexpected", but insisted the race was not over.
"I admit I was convinced I would win in the first round," he said on Sunday. "The game is about to start. We are in extra time. In extra time, we will win over the Brazilian people."
The president of Brazil's supreme electoral court said on Sunday that no evidence of international interference was found in the election.
President Lula made "sovereignty" a key pillar of his campaign and at times accused the US of trying to interfere in and influence Brazil's elections - which the US has denied.
Earlier this year, Bolsonaro successfully lobbied the US to designate the two biggest Brazilian gangs as terrorist organisations.
Last year, Donald Trump used the coup trial of Jair Bolsonaro as justification for imposing tariffs on Brazil and sanctioning some top officials and judges.
A win for Flávio Bolsonaro would likely see Brazil join the US's "Shield of Americas" coalition against narco-trafficking and align more closely with the US.
Lula has criticised the US terrorist designation of Brazilian gangs but launched various reforms to tackle the financial networks of organised crime networks, improve homicide investigations, and invest in prisons.
The economy has also been central to this campaign: the country has high levels of personal debt and slowing growth.
Lula has defined his legacy through a series of social welfare programmes, most notably Bolsa Família, that pays families to ensure children stay in education and receive healthcare such as vaccines, as well as building more universities. The programmes have been credited with lifting millions of Brazilians out of poverty.
He has also backed oil drilling exploration, which has proved controversial with environmentalists, but he has a record of tightening environmental protections and reducing the rate of deforestation in the Amazon. Deforestation increased significantly under Jair Bolsonaro's presidency.
Flávio Bolsonaro has pledged a public debt ceiling and government spending cuts, a revision of social welfare, and to bolster the critical minerals sector.
