Jair Bolsonaro has been detained after authorities found he posed a concrete flight risk while under home confinement.
The ex-president was convicted of planning a government overthrow in September and handed more than 27 years in prison, but he remained under confinement pending legal challenges.
Top Judicial Official Justice Moraes said the decision to arrest the elderly politician was a preventative measure after fresh information came to light.
This encompassed seeking to disable his ankle monitor and a call for a demonstration that could facilitate a chance to flee".
In a paperwork permitting the detention, the magistrate said information from the centre monitoring the former president's confinement suggested the one-time head of state's plan to remove the electronic ankle bracelet to secure accomplishment in his flight.
This, it said, would be "facilitated by the chaos caused by the gathering called by his offspring.
His child, Flávio, who works as a senator, called for a assembly of his backers near the former president's residence to take place on Saturday night.
The senator wrote on social media on Friday: "Are you going to fight for your country, or watch it all from your mobile device there on your settee? I invite you to fight with us."
He said the demonstration would be so followers could "pray for his health and for the restoration of democratic rule in our land."
Part of the magistrate's decision was the chance of his transfer to foreign missions near the home, considering that the investigations revealed a background of organizing to seek refuge through a consular facility", a announcement said.
The court filing emphasizes that the American diplomatic mission in the national capital, Brasilia, is situated around 13km from his dwelling.
Bolsonaro's legal woes have drawn the ire of fellow right-wing populist US President Donald Trump, leading him to impose a half-rate duty on goods coming from Brazil.
He is being held in a national police facility in Brasilia and will have a imprisonment assessment on the next day.
It was only on last Friday that the his legal team asked the Top Court to authorize him to serve his whole jail sentence under home confinement, with electronic monitoring.
They also requested that the former president be permitted to depart his residence for medical care, saying he required frequent medical attention for respiratory ailments and other health problems.
He was convicted of leading a conspiracy aimed at retaining his authority after he failed to win the 2022 election to his ideological adversary, Luiz Inácio Lula da Silva.
High Court judges said that he was aware of a plot which included plans to assassinate the current president and his vice-presidential running mate, Geraldo Alckmin, and to detain and kill Alexandre de Moraes - the Supreme Court justice who has been managing Bolsonaro's trial.
The plot was stopped because it failed to get the endorsement of the army and air force commanders. Lula was took office without issue on the first day of 2023.
But a week later, on the eighth of January, many Bolsonaro supporters stormed and vandalised government buildings in the capital, Brazil's capital.
The police stepped in and around fifteen hundred individuals were taken into custody.
The judges found that the protesters had been provoked by the former president whose strategy, they said, was for the country's army to take action, bring back stability and reinstate his authority.
At the time, the legal team called the decades-long sentence "absurdly excessive.
He was also banned from seeking elected position until the year 2060 - a decade minus two years after the completion of his term.
The ex-leader called the trial a "witch hunt and said it was aimed at blocking him participating in the 2026 presidential election.
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