Former Brazilian President, Luiz Inacio Lula da Silva, was briefly detained for three-hour questioning in a federal investigation of a vast corruption scheme related to the state oil company Petrobras, fanning a political crisis that threatens to topple his successor, President Dilma Rousseff, Reuters reported.

According to investigators, evidence suggested Lula had received illicit benefits from kickbacks at the oil company, Petrobras, in the form of payments and luxury real estate.

Lula’s questioning in police custody was the highest profile development in a two-year-old graft probe centered on Petrobras, which has rocked Brazil’s political and business establishment and deepened the worst recession in decades in Latin America’s biggest economy.

The evidence against the former president brought the graft investigation closer to his protege Dima Rousseff. She is already fighting off impeachment for allegedly breaking budget rules, weakening her efforts to pull the economy out of recession.

There is much more at stake in these investigations than just Lula’s personal reputation, according to BBC. His legacy and the future of his political project for Brazil – which has been shaping the country for the past 14 years – are also under scrutiny.

Recently, it was also reported that Peruvian President, Ollanta Humala, could have received $3m in bribes from the large Brazilian construction company Odebrecht in exchange for contracts in Peru.