RIO DE JANEIRO – The Brazilian Attorney General’s Office on Friday presented additional charges against former President Luiz Inacio Lula da Silva, already the target of three indictments for corruption.

The latest accusation refers to alleged influence-peddling to benefit the former head of state’s son, Luiz Claudio Lula da Silva.

The purported illegal actions took place in 2013-2015, two years after the end of Lula’s second term as president, but prosecutors maintain that he continued to wield influence within the administration of protege and successor Dilma Rousseff.

Luiz Claudio Lula da Silva received 2.5 million reais ($740,000) from companies that sought an extension of favorable tax treatment for Brazil’s auto industry, according to the AG Office.

Lula Sr. also had a role in supposed irregularities in the Rousseff administration’s decision to purchase 36 jet fighters from Saab, the indictment claims.

Lawyers representing the former president denounced the new accusations as based on murky and secretive investigative procedures.

“Neither ex-President Lula nor his son took part in, or had any knowledge of, any action related to the purchase of fighter planes from the Swedish company Saab, nor with the extension of tax benefits,” attorneys Cristiano Zanin Martins and Roberto Teixeira said in a statement.

The AG Office is using “laws and judicial proceedings as a way of persecuting Lula and harming his political career,” the lawyers said.

Prior to the corruption charges, Lula was expected to be a candidate in the 2018 presidential election.

The earlier indictments dealt with Lula’s alleged acceptance of gifts from construction companies and a purported attempt to pay off a witness in the $2 billion corruption case centered on state oil company Petrobras.

News of the latest charges came as Lula joined Rousseff – ousted by Congress in August for ostensible budget irregularities – and former Argentine President Cristina Fernandez at a political conference in Sao Paulo.