Brasilia: Brazil's former Finance Minister Guido Mantega is under probe in connection with an ongoing investigation into a large corruption scam at state oil giant Petrobras, the media reported.
Mantega was arrested on Thursday but was released hours later due to his wife's illness.
Federal Judge Sergio Moro revoked the temporary arrest order, saying he was unaware that Mantega's wife was scheduled for surgery "due to a serious illness", Xinhua news agency reported.
All pertinent documents in his possession were seized by police during a search and seizure operation at his residence so he could not tamper with evidence, said Moro.
Prosecutors said Mantega asked for 5 million reais (about $1 million) to pay off the campaign debts of the Workers' Party, which was in power till May.
Mantega served as Finance Minister from March 2006 to December 2014, during ousted President Dilma Rousseff's second term.