Flávio Bolsonaro has not conceded defeat and has called for the election to be annulled

There is confusion about the whereabouts of defeated Brazilian presidential candidate Flávio Bolsonaro, after Brazil cancelled his passports and Argentine officials say he boarded a flight to Ecuador.

Sources had told the BBC earlier on Tuesday that Bolsonaro had arrived in the US.

But Argentine migration authorities later said he had crossed Brazil's land border with Argentina late on Tuesday night local time.

In a tweet, external, the migration authorities said that he, his wife and two daughters had boarded a private flight headed towards the city of Guayaquil in Ecuador shortly after crossing the border.

It is not clear whether Ecuador would be his final destination.

Earlier on Tuesday, a senior US official confirmed the US State Department would issue visas to Bolsonaro and his family and allow them entry into the country, were they to request them.

When reporters asked US President Donald Trump about Bolsonaro and his family's whereabouts later, he said: "I heard he was in Argentina."

Speculation about Bolsonaro's whereabouts started hours after Brazil's Supreme Court ordered Bolsonaro to surrender his passports amid an investigation into alleged money laundering. Bolsonaro has not been charged and has denied the allegations.

The court gave Bolsonaro a deadline of 24 hours to hand over the documents.

At the time, Bolsonaro said he had no plans to leave the country, and insisted that he would stay in Brazil to lead the opposition to his left-wing rival, President Luiz Inácio Lula da Silva, who on Sunday won the election.

After he missed the deadline - at around noon local time (15:00 GMT) on Tuesday - Brazilian officials cancelled the documents.

When BBC Brasil contacted his lawyers, shortly after the deadline to hand over his passports had expired, they insisted they were "completely in the dark" about his whereabouts.

Referring to speculation he had left the country, they said that "we knew nothing about this, and we still have no information about what happened," one lawyer said.

A police source told the BBC that Brazilian federal officials were checking border crossings to establish if Bolsonaro could have travelled to neighbouring Argentina.

At the time, Argentine authorities told the BBC there was no record of the senator entering their country through any border crossing.

Bolsonaro has not made any public statements since Monday afternoon local time, when he posted a video on social media.

He was already under investigation for alleged corruption over the financing of a film about his father, former President Jair Bolsonaro, who was convicted of plotting a coup and is under house arrest.

A separate inquiry involves alleged links to a Brazilian lawyer, who is accused of laundering more than $1bn through a fraud scheme.

Police said earlier this month they had discovered Bolsonaro had access to the bank accounts of a company owned by the lawyer.

Bolsonaro denied doing business with the lawyer, and described the passport confiscation as an attempt to intimidate him.

In addition to that investigation, Brazil's Supreme Court ordered police on Tuesday to examine Bolsonaro's electoral campaign over alleged foreign funding.

The 45-year-old senator suffered a stinging defeat on Sunday when he was beaten by Lula in a presidential run-off, which Bolsonaro had been widely expected to win.

His younger brother Eduardo Bolsonaro lives in the Texas, in the US, but was in Miami on Sunday, where he cast his vote at a polling station and attended an election viewing event which was streamed to his followers.

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Opinion polls had put him narrowly ahead of Lula and analysts pointed out that Bolsonaro's win in the first round of the election on 4 October, meant he was likely to take victory in the run-off.

But after an early lead in the count, he was overtaken by the veteran incumbent, who became the first presidential candidate to overturn a first round loss to win in the second round.

Lula won 51.79% of the vote, compared to Bolsonaro's 48.21%.

Despite trailing by 4.4 million votes, Bolsonaro has not conceded and has called for the election to be annulled.

He argues that he was put at a disadvantage because polling was extended by two hours on election day - even though the extension was requested by both his party and that of his rival.

He called the extension, which was ordered by a Supreme Court justice, a "dirty trick".

However the party he represented, the Liberal Party, has accepted the result, although it did say that the extension of voting "merits investigation".

Ayelén Oliva, Vinícius Mendes, Cecilia Barria Ricardo Senra and Ione Wells contributed to this report.

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