Sem Refino: Federal Police Search Ex-Governor Cláudio Castro Again in Rio Fuel-Fraud Case

Brazil · Justice

Behind the raids sits a fuel empire whose owner has fled abroad. And a court order freezing about R$52 billion in the group’s assets.

Operation Sem Refino, the Federal Police probe into fuel-sector fraud in Brazil. Has again put former Rio de Janeiro governor Cláudio Castro in its sights.

On Friday, agents carried out a fresh round of search warrants tied to the case. It was the third time this year that federal officers have knocked on doors linked to the ex-governor.

What Operation Sem Refino targets

Start with the basics. Sem Refino is a Federal Police investigation into fraud across Brazil’s fuel trade.

At its center sits Grupo Refit, the company behind the old Refinaria de Manguinhos in Rio. Because of its size, the case reaches deep into state government.

Investigators say the group dodged huge tax bills and hid money abroad. As a result, prosecutors treat it as one of the country’s biggest fiscal fraud cases.

Why police raided Cláudio Castro again

On Friday, agents fanned out across Rio de Janeiro state. Meanwhile, they carried 16 search warrants signed off by the Supreme Court.

Seven people were targeted, and the former governor was one of them. In fact, it was the third time since May that federal officers have searched addresses tied to him.

This second phase focuses on how environmental licences for the refinery were granted. Prosecutors suspect they were approved against the advice of technical staff.

The fuel scheme at the heart of the case

So what is Refit accused of doing. In short, of building a maze of companies to escape tax.

The group allegedly sold fuel while dodging ICMS, the main state sales tax. Meanwhile, it is said to have moved money offshore to hide the gains.

Refit is already known as one of Brazil’s largest tax debtors. Because of that, several states and the federal government have chased it for years.

How much money is in play

Now to the numbers, which are large. In the first phase, the Supreme Court froze about R$52 billion in the group’s financial assets.

At mid-August 2026 exchange rates, that is roughly US$10 billion. As a result, the companies’ operations were also suspended.

Separately, Refit is accused of evading around R$26 billion in taxes, about US$5 billion. So the sums at stake dwarf most Brazilian corruption cases.

The fugitive owner behind Refit

Refit is controlled by businessman Ricardo Magro. However, he has not been in Brazil to answer the accusations.

Magro lives in the United States, and a court has ordered his preventive arrest. Because he is abroad, his name was placed on an Interpol red notice.

That notice asks police worldwide to locate and detain him. Still, no arrest has been reported so far.

What Cláudio Castro is accused of

For Castro, the charge is not that he ran the scheme. Instead, investigators suspect he used the state’s machinery to favor Refit.

That points to tax breaks and licences handled by his administration. Although nothing has been proven, prosecutors see a pattern worth probing.

His defense says he was caught off guard by the raids. Moreover, it insists his government followed the law and technical advice.

How Castro went from governor to target

Castro is no longer the sitting governor of Rio. In fact, he left the Palácio Guanabara in March 2026.

He had been aiming for a Senate seat in the October election. Later, though, he pulled out of that race.

Since stepping down, he has faced a run of federal investigations. As a result, each new phase draws fresh political attention.

The officials swept up alongside him

Castro is far from the only name in the file. The first phase, back on May 15, brought 17 search warrants and seven removals from public office.

Those warrants ran across Rio, São Paulo and the Federal District. Meanwhile, the alleged scheme touched finance, environmental, legal and judicial bodies in the state.

In other words, prosecutors describe a network, not a lone actor. Because so many offices are involved, the case has rattled Rio’s political class.

What happens next

The investigation is clearly not finished. So more phases and more names could still follow.

For now, the seized phones and documents will be combed for evidence. After that, prosecutors must decide whether to file formal charges.

Castro, for his part, says he is cooperating fully. Still, the freeze on billions in assets keeps the pressure firmly on Refit.

More: Brazil news, every day from The Rio Times.

Frequently Asked Questions

What is Operation Sem Refino?

It is a Brazilian Federal Police investigation into fuel-sector fraud centered on Grupo Refit, the former Refinaria de Manguinhos. The first phase began on May 15, 2026.

Is Cláudio Castro still governor of Rio de Janeiro?

No. Castro left office in March 2026 and is now a former governor. He is a target of the probe, not the sitting governor.

How much money has been frozen?

In the first phase the Supreme Court blocked about R$52 billion, roughly US$10 billion, in the investigated companies’ financial assets.

What is Castro accused of?

Prosecutors suspect he used state machinery to favor Refit through tax breaks and licences. Nothing has been proven, and his defense denies wrongdoing.

Sources: Agência Brasil; G1; CNN Brasil; O Globo; JOTA.