Argentine President Alberto Fernandez said on Thursday he doubts that a prosecutor who died two days after accusing former president Cristina Kirchner of a cover up in the 1994 bombing of a Jewish community center committed suicide.
But he insisted "there isn't a shred of proof" that Alberto Nisman was murdered, as his family insists.
Nisman was appointed special prosecutor into the 1994 bombing of the Argentine Israelite Mutual Association (AMIA) headquarters, which left 85 dead and 300 wounded.
But in 2015, Nisman's body was found in his Buenos Aires apartment with a gunshot wound to the head, delivered at close range from a handgun found at his side.
The timing and circumstances of his death were suspicious: it came just days after he directly accused then-president Kirchner and some of her top aides of covering up Iran's alleged involvement in the bombing.
"I doubt that someone who was going through a euphoric moment could commit suicide, I don't know that. I'm allowing myself to doubt it," Fernandez, whose vice president is Kirchner, told Radio 10.
Nisman had been due to outline his case against Kirchner before Congress just two days after his death.
Kirchner, president from 2007 to 2015, is accused of having attempted to cover up Iranian involvement in the bombing in return for lucrative trade deals with her government.
In July, Fernandez testified in Kirchner's trial over a newspaper interview he gave in 2015 criticizing her for allowing Iranian suspects to be questioned back home, rather than in Argentina.
Although he was cabinet chief under Kirchner's husband and predecessor as president, Nestor Kirchner, and initially held onto the post under Cristina Kirchner, the two fell out and Fernandez became a heavy critic of the then president.
The two have since made up and Fernandez, a criminal law professor, told Radio 10 that the cover-up case against Kirchner was "absurd."
In the Nisman case, he said "the only person harmed by the crime was Cristina."
Nisman's accusation was twice dismissed before judge Claudio Bonadio took up the case in 2016, after Kirchner had been replaced by Mauricio Macri as president.