Alberto Nisman, the Argentine federal prosecutor who had led the investigation into the 1994 AMIA bombing since September 2004, was found dead in the early hours of Monday, 19 January 2015, in his 13th-floor apartment in the Torre del Parque building in the Le Parc Puerto Madero development, Buenos Aires. His mother had been unable to open the apartment door, and a locksmith opened a service door that had been locked from inside; Nisman's body was found on the bathroom floor, blocking the door, alongside a .22-caliber Bersa pistol and a spent bullet casing.
Nisman's death came hours before he was due to present a criminal complaint to the Criminal Law Committee of the Argentine Chamber of Deputies. In that complaint, filed 13 January 2015, he had accused President Cristina Fernández de Kirchner, Foreign Minister Héctor Timerman, deputy Andrés Larroque, and activists Luis D'Elia and Fernando Esteche of concealment, alleging the 2013 memorandum of understanding with Iran was intended to shield Iranian officials from responsibility in the AMIA bombing in exchange for improved trade relations. Interpol Secretary General Ronald Noble publicly disputed a key element of the allegation, stating on 15 and 18 January 2015 that Argentina had never requested the lifting of Red Notices against Iranian suspects and that Nisman's assertion on this point was false.
The autopsy documented a fatal gunshot wound; there were no signs of forced entry or physical struggle. A paraffin test on Nisman's hands showed no gunshot residue, though investigators noted this result was not conclusive given the weapon's caliber. Special Prosecutor Viviana Fein said no items at the scene indicated the presence of other people, but later reported that DNA from a second individual was recovered from a coffee cup in the kitchen sink. The pistol used belonged to Diego Lagomarsino, a computer technician employed by Nisman who had visited him the evening before his death and was, according to building security records, the last person known to have seen him alive. Lagomarsino could not explain the absence of his own fingerprints on the weapon.
Federal Judge Daniel Rafecas dismissed Nisman's underlying complaint against the president and others on 26 February 2015, finding it did not meet a minimum standard of scrutiny. In September 2017, Argentina's National Gendarmerie issued a forensic report concluding Nisman had been murdered, asserting he was beaten by two people before being shot — a finding that contradicted earlier suggestions of suicide. As of the most recent judicial review under Judge Julián Ercolini, the presumption of homicide has been formally upheld, though no material perpetrators have been identified; related side investigations, including alleged money laundering involving Nisman's relatives and Lagomarsino, remain stalled. Nisman's death prompted a large silent march on 18 February 2015, in which an estimated 400,000 people demonstrated in Buenos Aires.