Argentina marked one year on Monday since the mysterious death of prosecutor Alberto Nisman with calls for justice.Nisman was found dead under unexplained circumstances on January 18, 2015, after accusing Argentina's then-president, Cristina Fernandez, of trying to cover up Iran's alleged role in the 1994 bombing of Jewish community centre in Buenos Aires that killed 85 people. Days after his death, he had been slated to submit the formal report with the allegations against the government.Thousands gathered in the Argentine capital for a homage to Nisman, where many called for answers into his death."Forty millions Argentines need a society at peace to overcome the differences that plague us. Forty million Argentines want to know how the gun went off and who did it," said Ariel Cohen Sabban, president of the Israeli-Argentine association DAIA.Nisman was found in his apartment with a bullet in his head and a pistol by his side, just before he was due to testify to the Argentine congress about his findings.During the course of his investigation, Nisman alleged that the bombing was carried out by Iranian agents with deep ties to senior government officials in Tehran. Iran denies any involvement in the blast.Nisman suggested that Argentine officials were compromised because they had engaged in questionable and clandestine trade deals with Iran involving trading grain for cheap Iranian oil. It had been alleged that the Fernandez administration let up on the gas pedal on the investigation against the Iranians to facilitate the trade deal.For many, the fallen prosecutor has emerged as a symbol for the fight for justice in Argentina."If a prosecutor is killed or commits suicide then it should be investigated. The justice system needs to act. If it doesn't then what guarantees do we have. I have grandchildren," said resident, Susana Hubin.Local, Dalia Blungurt, told Reuters that Nisman was an example for future generations of Argentines."Don't forget someone who fought for justice because unfortunately this is something that's very rare in our country. Let this be an example and so that future generations also fight for justice, because it is very rare," she said.Fernandez, her administration and the government of Iran have denied involvement in the attack or any subsequent cover-up. Additionally, a judge cleared the president of the cover-up accusation.Fernandez and her ministers say a former spymaster, Antonio Stiuso, duped Nisman into fabricating unfounded allegations to destabilise the government and then needed him dead. They previously questioned whether the spy chief was working for the United States.Stiuso, who was operations chief of the now-disbanded Intelligence Secretariat, disappeared following Nisman's murky death last January, which plunged Fernandez's government into political turmoil.Argentina's new centre-right president, Mauricio Macri, has vowed to find out how the prosecutor died.On Sunday (January 17) the president, accompanied by his wife, Juliana Awada, and young daughter Antonia, met with Nisman's two daughters, Lara and Kala to commemorate their father's death in a private ceremony.It is still not known whether Nisman was murdered or committed suicide.