BUENOS AIRES, Argentina -- Former Argentine president Cristina Fernandez was indicted Tuesday in a corruption case involving public works.

Federal Judge Julian Ercolini approved charges of illicit association and fraudulent administration against Fernandez, and two former aides: former planning minister Julio de Vido and former public works secretary Jose Lopez.

Also named was businessman Lazaro Baez, whose Austral Construcciones company allegedly benefited from irregular contracts.

The judge's order froze the equivalent of up to $633 million of each defendant's assets, though it was not clear they have that much.

The ruling published by official Center of Judicial Information said the defendants are accused of associating to illegally take public fund meant for public works between May 2003 and December 2015, largely in the southern province of Santa Cruz.

The judge said 52 contracts worth about $2.9 billion were assigned to Baez's companies at prices that averaged 15 percent above the original budget.

Fernandez's late husband, Nestor Kirchner, was president from 2003 until 2007.

Fernandez made no immediate comment on the charge, but she repeatedly has denied wrongdoing and invited an audit of public works contracts during her administration.

Her attorney, Gregorio Dalbon, said on his Twitter account he was not worried about the indictment and said he would appeal.

Illicit association carries a possible 10 year prison sentence, while fraudulent administration can lead to six years behind bars.

Since leaving office in December 2015, Fernandez has alleged she is the victim of persecution by her conservative successor, Mauricio Macri.

In May, a judge indicted Fernandez on charges of manipulating currency exchange futures markets, allegedly causing economic damage to the government.