Brazil's new leftist government tightened the net around suspected instigators of riots that targeted the seats of power, ordering a probe of ex-president Jair Bolsonaro and arresting his justice minister Saturday.

Thousands of Bolsonaro backers broke into the presidential palace, Congress and Supreme Court buildings in the capital Brasilia last Sunday, demanding the ouster of his successor Luiz Inacio Lula da Silva.

They smashed windows and furniture, destroying priceless works of art, and left graffiti messages calling for a military coup.

More than 2,000 alleged rioters were detained, and the authorities are tracking those suspected of having masterminded and financed the revolt that shocked Brazil and the world.

Late Friday, a Supreme Court judge gave the green light for a probe into the origins of the riots to also look at Bolsonaro, who for years had sought to cast doubt on Brazil's internationally-hailed election system.

A request to add Bolsonaro to the suspect list had come from the office of the prosecutor general (PGR), which cited a video he had posted "questioning the regularity of the 2022 presidential elections."

By doing so, "Bolsonaro would have publicly incited the commission of a crime," a PGR statement said.

The request concerned an ongoing investigation into the "instigation and intellectual authorship" of the rioting.

Bolsonaro has never publicly acknowledged Lula's victory and left for the United States, where he remains, two days before his successor's inauguration.

The far-right ex-president's last justice minister, Anderson Torres, who was also in the United States when the riots happened, was arrested early Saturday on his return to Brasilia.

Torres is the subject of a Supreme Court warrant for alleged "collusion" with the rioters, and stands accused of "omission" in his most recent job as security chief for the capital.

- Denial -

Brazil's Federal Police on Saturday said it had executed a warrant for Torres' "preventive detention."

It said he "was arrested upon landing at Brasilia Airport and sent to custody, where he will remain at the disposal of Justice. The investigation remains confidential."

The Folha de S. Paulo daily reported that Torres had made an initial court appearance, and was expected to give testimony next week. He was being held at a military police facility.

Lula's new justice minister Flavio Dino on Friday confirmed the discovery at Torres' home of a draft decree proposing emergency steps for the possible "correction" of the October election, which Lula had won by a razor-thin margin.

The draft, published in a newspaper, bears Bolsonaro's name, but Dino said the authorship was unknown. It is not known if it was compiled before or after the election.

Dino said the document connected the dots between Lula's October 30 election victory and the January 8 riots.

It was, he said, a "fundamental element for understanding cause and effect," a "missing link between a succession of events, showing that they were not isolated. And yes, that there was... a plan."

Lula and Dino have both said the violence could not have happened without collusion from members of the security forces.

Torres said on Twitter the document was "likely" part of a pile of papers that were destined to be destroyed.

He added the contents of the draft had been taken "out of context" to "feed false narratives" against him.

Torres and Bolsonaro have both denied involvement in the January 8 riots.

But the PGR said Bolsonaro's Facebook video -- even though posted two days after the uprising and later removed -- may serve as "a probative connection" that justified "a global investigation of the acts performed before and after January 8, 2023 by the defendant."

Dino said Friday there were no extradition proceedings against Bolsonaro.

- 'Infiltrators' -

In a note sent to AFP, Bolsonaro's defense blamed the violence on "infiltrators" and said he "never had any relationship or participation in these movements."

In the wake of the violence, many rioters claimed -- without evidence -- that left-wing agitators were the real culprits, just as in the United States when some on the right blamed the far-left Antifa for the storming of the Capitol on January 6, 2021.

Many of the rioters were fueled by Bolsonaro's anti-"communism" rhetoric against Lula, who had served two previous terms as president from 2003 to 2010.

They are also deeply distrustful of Lula and the PT after a massive corruption scandal that saw him serve time in jail before having his conviction overturned.

The attorney general's office has identified 52 individuals and seven companies suspected of having helped pay for transport and food for the rioters.