Bolsonaro has been arrested after authorities found he posed a concrete flight risk while under house arrest.
The one-time leader was found guilty of planning a military coup in last fall and given more than a 27-year term in jail, but he remained under house arrest pending court reviews.
High Court Judge Alexandre de Moraes said the action to imprison the septuagenarian politician was a precautionary step after "new facts" came to light.
This encompassed seeking to disable his tracking device and a summons to a supporters' gathering that could facilitate a potential flight.
Judicial Records Show Escape Concerns
In a filing authorising the custody, the magistrate said intelligence from the facility tracking his home detention suggested the ex-president's aim to disable the electronic ankle bracelet to secure accomplishment in his getaway".
This, it said, would be assisted by the disorder caused by the gathering called by his child.
His child, Flávio Bolsonaro, who holds office as a congressional representative, called for a meeting of his followers near his father's house to take place on Saturday evening.
His son wrote on social media on the previous day: Will you battle for your nation, or observe everything from your smartphone there on your sofa? I invite you to battle with us."
He said the vigil would be so supporters could "pray for his health and for the reestablishment of democratic governance in our nation."
Diplomatic Refuge Fears
Part of Justice Moraes's determination was the chance of the former president's "relocation to diplomatic missions near the home, considering that the inquiries revealed a history of arranging to seek refuge through a embassy office", a declaration said.
The court filing emphasizes that the United States embassy in the federal district, Brasilia, is situated around 13km from his dwelling.
Global Responses
The former president's legal troubles have generated frustration from fellow right-wing populist United States President Donald Trump, causing him to implement a 50% tariff on Brazilian product imports.
The former president is being held in a federal law enforcement building in Brazil's capital city and will experience a custody hearing on the following day.
Recent Legal Requests
It was only on last Friday that the ex-leader's attorneys asked the High Court to permit him to fulfill his full incarceration period under house arrest, with tracking devices.
They also requested that Bolsonaro be allowed to depart his residence for medical treatment, saying he demanded frequent medical attention for lung conditions and other illnesses.
Background on Conviction
He was determined responsible of leading a plot aimed at retaining his authority after he lost the 2022 election to his ideological adversary, President Lula.
High Court judges said that he was aware of a scheme which included plans to murder his opponent and his VP candidate, his vice-presidential candidate, and to detain and kill the presiding judge - the High Court judge who has been overseeing Bolsonaro's trial.
The plot was prevented because it couldn't obtain the endorsement of the army and air force commanders. His successor was took office without incident on 1 January 2023.
But a following week, on the eighth of January, numerous his backers stormed and vandalised public facilities in the federal district, Brazil's capital.
The law enforcement stepped in and around 1,500 people were taken into custody.
The judges found that the protesters had been provoked by Bolsonaro whose strategy, they said, was for the country's army to intervene, reestablish control and return him to office.
At the period, the legal team called the 27 years and three months sentence unreasonably severe".
He was also barred from campaigning for office until the year 2060 - a decade minus two years after the end of his sentence.
The former president called the court case a political persecution and said it was aimed at blocking him competing in the next presidential race.
