The far-right firebrand was sentenced to 27 years in prison over a scheme to stop leftist Luiz Inacio Lula da Silva from taking office after the 2022 elections -- a ruling he is still appealing.

Supreme Court judge Alexandre de Moraes said Bolsonaro's arrest was a preventive measure as he is a "high flight risk," and not the execution of his sentence.

Bolsonaro, who governed Brazil from 2019 to 2022, was placed under house arrest in August and has been confined to an upscale condominium in the capital Brasilia.

In his ruling, Moraes said that a planned vigil outside the condominium called by the former leader's son Flavio Bolsonaro on Saturday could cause turmoil that would "create an environment conducive to his escape."

Flavio urged supporters to "fight for your country" in a video calling for the vigil.

The judge said there had been an "attempt to break" Bolsonaro's ankle bracelet early Saturday as part of a plan to "ensure the success of his escape, facilitated by the confusion caused by the demonstration called by his son.

Moraes also highlighted the proximity of Bolsonaro's home to the US embassy, adding the far-right leader had previously planned to flee to the Argentine embassy to request political asylum.

Bolsonaro is an ally of US President Donald Trump, who said his trial was a "witch hunt" and imposed punitive tariffs and sanctions against Brazil in retaliation.

In a statement, Bolsonaro's defense team said his detention caused "deep perplexity" as it was based on a "prayer vigil."

They said they would appeal the detention which "could put his life at risk" due to his alleged frail health.

- Champagne and anger -

Bolsonaro has been taken to a federal police complex in Brasilia where prisoners undergo medical examinations before being sent to jail, according to a source close to the case.

Another source sent a video to AFP showing the small room where Bolsonaro will be held for now, with a television, air conditioning and a mini-fridge.

A group of women gathered outside the location and uncorked a bottle of sparkling wine to celebrate Bolsonaro's imprisonment.

Ana Denise Sousa, 47, a high school philosophy teacher, told AFP outside the prison she was overjoyed.

"The biggest scoundrel, the worst guy...who screwed everyone over, who (attempted) a coup, who never felt pity for anyone -- and now he's going to pay."

Meanwhile supporters arrived draped in Brazil's green and yellow flag.

Sao Paulo Governor Tarcisio de Freitas said Bolsonaro's detention "violates the principle of human dignity" and vowed to fight to rectify the "injustice".

Bolsonaro's legal woes have left Brazil's large conservative electorate without a champion heading into 2026 presidential elections, in which Lula, 80, has said he will seek a fourth term.

Bolsonaro's fervent evangelical wife Michelle wrote on Instagram that she trusted "the Lord will provide the way out."

- Time running out -

Bolsonaro, a former army captain, is adored by many for his conservative values and gloves-off style.

However he drew criticism for vitriolic comments about gays and women and for praising Brazil's dictatorship years.

During his presidency he was praised for his handling of the economy, but slammed for overseeing record Amazon deforestation and dismissing Covid-19 as a "little flu".

He was convicted in September of leading a criminal organization that conspired to ensure his "authoritarian hold on power."

The plot involved a plan to assassinate Lula, his vice president Geraldo Alckmin, and Moraes.

An appeal of his sentence was rejected last week.

On Friday, Bolsonaro's lawyers said they would file further appeals before a Monday deadline.

However, they requested he be allowed to serve his sentence under house arrest due to ill health. Moraes rejected this petition Saturday due to the change in events.

Bolsonaro, 70, suffers ongoing consequences of a stab wound to the abdomen received during a knife attack on the campaign trail in 2018 and has required several follow up surgeries.