The investigation reopened after the 2015 assassination of prosecutor Alberto Nisman who conducted the original investigation.
A federal court in Argentina ruled that former President Cristina Kirchner be placed in preventative custody, and that the Senate strip away her parliamentary immunity. Still a key figure in the Argentine left, she blamed her major political antagonist, President Mauricio Macri, a center-rightist, for orchestrating "these maneuvers and ... persecution".
Cristina Kirchner is being investigated for her role as president in signing a 2012 pact with Iran, agreeing that officials suspected of involvement in the bombing could be investigated in their own country and not brought to Argentina. But Argentine officials are investigating the possibility that Nisman was killed.
Argentina's justice department has been unable to determine whether he died by suicide or murder, as his family maintains. Nisman's body was discovered hours before he was scheduled to brief Congress on the community center bombing.
The agreement provided for the creation of a supposed Investigative Commission whose central objective was to exculpate the Iranian defendants by suggesting an alternative explanation for the attack.
Fernandez said on December 7 that the deal with Iran "was an act of foreign policy that can not be prosecuted".
The prosecutor in the case, Gerardo Pollicita, said he believes Kirchner led a criminal plot to help provide impunity for Iranian nationals who attacked the AMIA headquarters.
"The case was absolutely paralyzed because Iran does not extradite its compatriots". She was sworn in as a member of the Senate last week. For that to happen, two-thirds of the legislators must decide to remove Kirchner's immunity for an arrest. The Senate usually avoids votes to allow the arrest of colleagues until they have been found guilty, but Senate leaders have said they will closely examine the judge's ruling.
The treason allegation unveiled Thursday represented the first time that a judge had requested Fernandez's arrest.
Fernandez and the other defendants have several options to appeal, which could drag the case out for years.