Alberto Nisman was discovered lying dead in his bathroom in the early hours of Monday morning, with a handgun by his side. Initial reports suggested suicide.
The veteran prosecutor had spent the past two years compiling a 300-page case on the 1994 bombings of the Argentine Israelite Mutual Association building (AMIA), which killed 85 people. Iran has long been suspected as being behind the bombings.
Mr Nisman has accused Mrs Kirchner and her foreign minister, Hector Timerman, of attempting to "erase" Iran's role in the attack, in return for favourable oil deals.
"The president and her foreign minister took the criminal decision to fabricate Iran's innocence to sate Argentina's commercial, political and geopolitical interests," he said. '