Former president Carlos Menem on Thursday was charged with obstructing the probe into the 1994 bombing of a Jewish charities building in Argentina that killed 85 people.
Some 300 people were also wounded in the attack on the Argentine Jewish Mutual Association (AMIA) in Buenos Aires.
Menem, 79, was a two-term president (1989-1999) from the ruling Peronist party. He also faces charges in a separate case involving his role in a scheme to smuggle weapons to Croatia and Ecuador while both countries were involved in wars in the 1990s.
Argentina has South America's largest Jewish community.
Argentine officials claim that Iran orchestrated the attack and that the Iranian-backed Hezbollah carried it out. The United States and Israel also say Iran is behind the bombing, but Iran has denied it.
Interpol said in 2007 it would help Argentina seek the arrest of current Iranian Defense Minister Ahmad Vahid and four other prominent Iranians wanted in connection with the attack.
Among the other suspects is Mohsen Rezaei, who ran against President Mahmoud Ahmadinejad in the June 12 presidential election and is a former leader of the Revolutionary Guard.
Other wanted Iranians in the case are former intelligence chief Ali Fallahian; Mohsen Rabbani, former cultural attaché at the Iranian Embassy in Buenos Aires; and former diplomat Ahmad Reza Asghari.