RIO DE JANEIRO >> Former Brazilian President Michel Temer remained silent when questioned by investigators today, a day after he was arrested as part of the country’s sprawling Car Wash corruption probe.

The probe has ensnared several top politicians and businessmen in the South American country, including former President Luiz Inacio Lula da Silva, who is currently serving a 12-year sentence.

Temer, 78, was arrested on corruption charges Thursday, with prosecutors saying that construction company Engevix paid him bribes in exchange for a contract to build a nuclear power plant in the city of Angra dos Reis in the southern part of Rio de Janeiro state.

Federal prosecutor Fabiana Schneider told journalists that Temer’s attorneys said he would not answer any questions. She said she is “absolutely convinced” the former president needs to be jailed so investigations can go forward.

“The Car Wash task force has been very restrained in its requests for arrest,” Schneider said. “We are talking about a criminal organization that has robbed the taxpayer for 40 years.”

Lawyers for the former president consider his jailing illegal and have filed two requests for his release. A federal court based in Rio de Janeiro postponed a ruling to next Wednesday.

Temer’s former Cabinet minister, Wellington Moreira Franco, was also arrested and has denied any wrongdoing.

Both of their arrests come at a time of considerable tension between Car Wash prosecutors and Brazil’s top court. A week ago, the nation’s Supreme Federal Tribunal ruled that some graft investigations should be handled by electoral judges because they involve politicians who allegedly received kickbacks from companies to finance their campaigns.

In ruling, some justices acknowledged that Brazil’s electoral court system lacks the infrastructure and expertise to handle such big corruption cases, but expressed confidence that the gap could be bridged.

The country’s top court also blocked a move that allowed the Car Wash task force to manage hundreds of millions of dollars recovered from corruption scandals at state-run oil giant Petrobras.

While prosecutors and judges involved in the investigation see the imprisonment of Temer as a major win after those setbacks, however, others in Brazil — including adversaries of the ex-president — were critical of the decision of federal Judge Marcelo Bretas to arrest him.

“Car Wash is trying to turn the focus away from the discredit it was falling into,” said former President Lula da Silva on Twitter Thursday night. “The (Car Wash) task force does not need pyrotechnics to survive, it needs sobriety.”

Luis Henrique Machado, a law professor at IDP university in Brasilia, said the arrest of deeply unpopular Temer on “absurd grounds” appeared to be a response to recent blows by courts.

“Prosecutors and magistrates have pressured and intimidated Brazil’s Supreme Court recently. That game is being played,” Machado said. “It is a judicial invention that could cost all sides dearly.”

This is not the first time that Bretas, who is in charge of all Car Wash cases in the state of Rio de Janeiro, has come under fire. Bretas is also behind the arrests of ex-Rio de Janeiro Gov. Sergio Cabral and Brazilian businessman Eike Batista, once number eight on Forbes’ World’s Billionaires list. In 2016, he sentenced then president of state-run Eletronuclear, Othon Luiz Pinheiro da Silva, to 43 years in prison.

Supporters of Bretas see him as serious, firm and uncompromising, while adversaries consider him to be a zealot with political ambitions.

Temer governed between 2016 and 2018 after his predecessor Dilma Rousseff was impeached.

His administration was clouded by corruption allegations, with the former president himself surviving two votes in Congress that would have suspended him from office and put him on trial for graft charges.

There are now 10 investigations related to Temer, who was once a discreet backroom dealmaker in Congress before he was propelled into Brazil’s presidency amid a huge political and economic crisis.

Temer left office with his job approval in single digits, and many of adversaries were sure that his imprisonment was imminent.