SAO PAULO (AP) — Brazil's Supreme Court has ruled that some corruption cases will be tried by electoral courts, a decision that prosecutors say will have dire consequences for a sprawling graft probe roiling Latin America's largest nation.

In a 6-5 ruling, the top court decided Thursday night that electoral courts should handle cases that involve "Caixa 2," the term used to describe campaign financing via bribes.

Launched in March 2014, the so-called Car Wash probe has uncovered schemes in which companies received bloated contracts and then kicked back billions in bribes to officials. Investigations have led to the jailing of top political figures, such as former Brazilian President Luiz Inacio Lula da Silva, former Chamber of Deputies Speaker Eduardo Cunha and former Rio de Janeiro Gov. Sergio Cabral. They have also caused political impact in Peru, Panama and El Salvador.

But many legal analysts, business leaders and politicians accuse Car Wash prosecutors of judicial overreach in favor of a political agenda, which prosecutors deny.

The court ruling Thursday said that some cases should be tried by electoral courts because they involve politicians who received kickbacks from companies to finance their campaigns.

Lead Car Wash prosecutor Deltan Dallagnol tweeted that "the fight against political corruption that began five years ago is coming to a close," suggesting that sending complex white-collar cases to electoral courts is essentially a way to ensure that nothing happens.

Dallagnol has been seen to be taking on an even larger role in the probe since former federal Judge Sergio Moro became justice minister for far-right Brazilian President Jair Bolsonaro at the beginning of this year.

Justice Gilmar Mendes, who voted in the majority, said efforts to sway the Supreme Court not to send cases to the electoral justice system amounted to methods used by "gangsters."

"This is a fight for power," said Mendes, a longtime critic of the Car Wash probe.

Several justices said Brazil's electoral court system lacks the infrastructure and expertise to handle big corruption cases.

Justice Luis Roberto Barroso disagreed with the majority but said the country would find ways to revamp its justice system and put Car Wash cases on trial.

Justices noted that electoral court judges could still revoke their right to prosecute such cases and send them to Brazil's criminal justice system.