The head of a global prosecutors group on Monday demanded an independent investigation into the death earlier this year of the Argentine prosecutor looking into the bombing of a Jewish community center in Buenos Aires.
Alberto Nisman was found dead under unexplained circumstances in January after accusing Argentina's president, Cristina Fernandez Kirchner, of trying to cover up Iran's alleged role in the 1994 bombing.
Nisman was found in his apartment with a bullet in his head and a pistol by his side.
Kirchner, her administration and the government of Iran have denied involvement in the attack or any subsequent cover-up.
Additionally, a judge has cleared the president of the cover-up accusation.
Gerhard Jarosch, the International Association of Prosecutors' (IAP) president and a deputy chief prosecutor in Vienna, told prosecutors meeting in Zurich that Nisman's death was one of the highest-profile recent examples of how prosecutors around the world are being threatened and sometimes losing their lives for doing their jobs.
Prosecutors have recently been killed in Egypt, Uganda, Honduras and Turkey, Jarosch said while speaking in Zurich at the opening ceremony for the IAP's annual conference that is being attended by U.S. Attorney General Loretta Lynch.
Nisman was found shot in his residence in Buenos Aires on Jan. 18, just before he was due to testify to the Argentine congress about some of his findings.
Nisman had just finished a report alleging that Fernandez' administration was involved in interfering with or covering up evidence related to the Jewish center bombing, in which 85 people were killed.
Last month, former Argentine President Carlos Menem failed to appear at the opening of his trial for allegedly conspiring to derail an investigation into the 1994 bombing.
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.
Nisman suggested that Argentinian officials were compromised because they had engaged in questionable and clandestine trade deals with Iran involving trading Argentinian grain for cheap Iranian oil.
In calling for Nisman's death to be investigated, Jarosch also asked prosecutors attending the event to sign a declaration seeking greater protection for prosecutors around the world.