Brazil on Tuesday formally charged ex-presidents Dilma Rousseff and Luiz Inacio Lula da Silva with racketeering for plotting to skim funds from Petrobras, the state oil giant.
The news is particularly bad for the uphill battle Lula is waging to win the presidency again. Rousseff was Lula's designated successor, and Brazil's first woman president.
"The crimes are believed to have taken place at least from mid-2002 to May 12, 2016" when Rousseff was suspended as part of impeachment proceedings, the attorney general's office said.
Their Workers' Party allegedly fleeced $475 million in bribe money, "making use of public entities including Petrobras, the National Development Bank (BNDES) and the Planning Ministry," according to the charges.
Attorney General Rodrigo Janot alleged that much of what became a transnational graft operation was run by Lula.
Dozens of senior leaders across the political spectrum and high-ranking businessmen have been investigated or convicted since the sprawling "Car Wash" corruption scandal broke in 2014.
The investigation has centered on Petrobras, where inflated construction contracts were used by business leaders and politicians to siphon off billions of dollars.
In July, Lula was convicted of graft -- and vowed an appeal -- in the largest scalp yet of the investigation and a stunning blow to the leftist's prospects for political comeback.