The far-right senator Flávio Bolsonaro has not been seen since Monday and missed a Tuesday-morning deadline to hand his passport to the federal police, fuelling rumours that he may have fled Brazil after losing Sunday’s presidential election.

A supreme court justice cancelled Bolsonaro’s passport minutes after the result in a ruling related to a criminal case against the senator. He until 11am to surrender the document to the federal police, but did not appear.

The Argentinian news website Infobae reported that on Monday night he reportedly fled to Argentina, where he was expected to board a private jet in Puerto Iguazú bound for the US, but the plane did not take off.

Bolsonaro, who has yet to concede defeat to Luiz Inácio Lula da Silva, posted a video on Monday in which, commenting on the cancellation of his passport, he said: “I never thought about leaving the country.”

One of the senator’s brothers, the former congressman Eduardo Bolsonaro, who is in self-imposed exile in the US, had said in an interview last Friday that his brother should leave Brazil if he lost.

The Brazilian newspaper Folha de S Paulo reported that allies in the Bolsonaro family’s inner circle had been told that he had indeed left for Argentina and intended to travel from there to the US.

As there is no record of him passing through any regular Brazilian immigration checkpoint, the federal police are trying to establish from Argentine authorities whether there is any record of him entering the country.

The Argentine channel Todo Noticias reported that the senator had reportedly crossed the border into Argentina on foot and abandoned plans to board the plane once news of his movements leaked.

Bolsonaro was told to surrender his passport over a criminal case in which the federal police are investigating him for possible involvement in a money-laundering scheme worth about £680m ($905m) involving betting companies.

The senator’s possible flight makes the future of the far right after the presidential election even more uncertain. The family patriarch, Jair Bolsonaro, is under house arrest for attempting a coup, and one of his sons is in the US and the whereabouts of another unclear.

Eduardo Bolsonaro has an outstanding arrest warrant against him in Brazil, after being sentenced to four years in prison for trying to interfere in his father’s trial by lobbying Donald Trump to impose sanctions on the justices hearing the case.

Political scientist Magna Inácio, a professor at the Federal University of Minas Gerais, believes a power vacuum may now emerge within the right.

“The resistance of Brazilian voters to handing victory to this more extremist camp sends a signal that the right leadership is now up for grabs,” she said.

Since Jair Bolsonaro, then a career congressman with few laws to his name, surprisingly won the presidency in 2018, there has effectively been no right wing in Brazil, only the far-right Bolsonarismo movement.

Camila Rocha, a political scientist who studies Brazil’s new right, believes the fact that three Bolsonaros are now potentially out of the picture could trigger a “shift in power” away from blood ties.

“I think there is a tendency for power to move away from the sons,” said Rocha, noting that before the election, polls showed Jair Bolsonaro supporters preferred other potential candidates over his eldest son, including Jair Bolsonaro’s wife, Michelle Bolsonaro, who was recently elected senator, and the São Paulo governor, Tarcísio de Freitas.

Flávio Bolsonaro reportedly did not want to run because he thought a presidential campaign would turn his life into “hell”, and believed his re-election to the senate was assured. But with Eduardo, his father’s “plan A”, now living in the US, the senator was chosen to run.

Most observers agree that Flávio lacks his father’s charisma. He had a 24-year political career in which he passed very few laws as a state legislator and senator, and the only previous time he ran for executive office was for mayor of Rio de Janeiro in 2016, when he fainted during a televised debate and finished fourth.

Even in a family frequently embroiled in legal trouble he stood out, facing longstanding criminal allegations, including suspicions that he embezzled part of his staff’s salaries, as well as more recent accusations.

Even so, 48.21% of Brazilians voted for Flávio Bolsonaro on Sunday, which many analysts see as both an anti-Lula vote and a vote for whomever Jair Bolsonaro had chosen.

Inácio believes the struggle over the Bolsonaro legacy will also play out among family members who remain in Brazil, including Michelle and Bolsonaro’s other political sons, the senator-elect Carlos Bolsonaro and congressman-elect Jair Renan Bolsonaro, who publicly do not get along with their stepmother.

“Michelle clearly has a political project of her own, but she is likely to face strong resistance from the two stepsons who are in congress. It is only a matter of time before tensions between them grow,” said the political scientist.