The Trump-allied former president of Brazil, Jair Bolsonaro, has been taken into police custody days ahead of the scheduled start of a 27-year prison term amid reported fears that he would try to escape from house arrest in the interim.

An aide to Bolsonaro confirmed to the Associated Press that the arrest took place around 6 a.m. on Saturday, hours after a Supreme Court justice with jurisdiction over the case stated that an ankle monitoring bracelet had been violated shortly after midnight.

Bolsonaro was removed from his house in an upscale gated community to the federal police headquarters at Brasilia, the capital, Andriely Cirino told the AP.

Fears of an escape attempt were heightened by reports of a planned large demonstration outside Bolsonaro’s home, organized by his eldest son.

The Supreme Court said it had received information about the “summoning of supporters” to the demonstration, which could “reach a large scale” and last for several days, CNN Brasil reported. The court said the vigil indicated a “high possibility of an attempted escape.”

Bolsonaro, Brazil’s right-wing president from 2019 to 2023, was sentenced in September to 27 years in prison on charges of plotting to illegally remain in power after losing a 2022 election to the current president, Inacio Lula da Silva.

President Trump, who has long railed over his own prosecution after America’s 2020 election, has called the two cases “very similar” and imposed a punitive 50-percent tariff on Brazil in response.

The justice who ordered the arrest, Alexandre de Moraes, was quoted saying he feared that Bolsonaro would try to flee to one of the foreign embassies in the neighborhood where he lived and seek political asylum.

“That information shows the intent of the convict to break the ankle monitoring to assure his escape is successful, which would be made easier by the confusion that would be caused by a demonstration organized by his son,” the justice said.

The arrest decision is to be reviewed in an extraordinary session of the Supreme Court on Monday.

A lawyer and former press adviser to Bolsonaro, Fabio Wajngarten, challenged the court’s claim that the ankle monitor had been tampered with, insisting in a posting to X that it was still working Saturday morning.

“How could something that was broken, violated, be functioning normally nine hours later?” he wrote. “The president had dinner – a soup – yesterday with four brothers and brothers-in-law, took medication for hiccups, felt drowsy and lay down around 10 p.m. None of his sons were at the house.”

Supporters of the former president, who insist on his innocence, are now expected to demonstrate outside the federal police headquarters over the weekend.