Eduardo Cunha, the former speaker of Brazil’s lower house, is accused of corruption, money laundering and tax evasion related to an oilfield purchase that Petrobras made in 2011 in the west African nation of Benin, among a series of other charges.
Mr Cunha was arrested in the capital, Brasilia, and taken to the southern city of Curitiba, where the probe into a sprawling embezzlement and bribery ring at flagship state oil company Petrobras is based.
Prosecutors said in a statement they had requested Mr Cunha’s detention on the grounds he represented a threat to the integrity of the investigation and was a flight risk. They also asked for bank accounts he holds totalling more than $60 million to be frozen.
A police spokesman told AFP: “We can confirm that [Mr Cunha] was detained in Brasilia.”
Mr Cunha, 58, denies all the charges. “This is an absurd decision, without motive,” he said in a Facebook post.
Part of Brazil’s growing conservative evangelical movement, Mr Cunha spearheaded Rousseff’s removal from office in August on charges that she broke government budget laws.
Rousseff, from the leftist Workers’ Party, lost her effort to stay in power after a year-long struggle as senators voted 61-20 to remove her. She was replaced by Michel Temer from Cunha’s own center-right PMDB party.
Following corruption allegations Mr Cunha was stripped of his congressional seat in September, losing his parliamentary legal privileges.
Anti-corruption judge Sergio Moro said he had ordered the arrest because there was “a real possibility of [Mr Cunha] fleeing the country as he has resources hidden abroad”.
The fact that he has dual Brazilian and Italian citizenship also increased the risk of him trying to evade justice, added Mr Moro.
Mr Cunha has been detained for an indeterminate period.
Mr Cunha’s arrest signals that the Petrobras corruption probe is set to continue.
Dozens of politicians – from the Workers’ Party but also numerous political figures on the right – as well as business executives have already been charged or convicted in the embezzlement and bribery scheme.
Ms Rousseff’s presidential predecessor, the leftist icon Luiz Inacio Lula da Silva, faces three corruption-related court cases, and speculation is rife that he may also be placed in pre-trial detention.