Argentina’s Jewish community last week commemorated the third anniversary of the death of Alberto Nisman, the special prosecutor whose demise has now officially been ruled as murder.

Nisman was found shot dead in the bathroom of his Buenos Aires apartment on January 18, 2015, after he had accused then-president Cristina Fernández de Kirchner of working to clear Iran of responsibility for a Jewish community centre bombing in 1994.

His death, which was initially called a suicide, happened the day before he was due to formally make his allegations against Ms Kirchner in parliament.

It caused a political storm in Argentina that continues to rage today.

Last week, members of Nisman’s family — including his mother, Sara Garfunkel and his two daughters — gathered at a private graveside ceremony at Buenos Aires’ Jewish cemetery, La Tablada, where he lies buried alongside many of the victims of the 1994 Amia centre bombing.

The car bomb at the Jewish centre caused a building collapse that killed 85 people and injured more than 300, in one of the worst antisemitic attacks seen since the Second World War.

It was when Nisman began investigating the bombing three years later that he and his daughters were sent multiple death threats, including gruesome photographs threatening consequences for him and his family. He was insulted, often called a “Zionist” and a “dirty Jew”.

His investigation made slow progress: it took a decade for the judiciary in Buenos Aires to issue an international warrant for the arrest of eight Iranian diplomats and one Lebanese accused of being behind the bombing. 

When Nisman died suddenly in 2015, a string of explanations were made. Ms Kirchner initially said that he had committed suicide, then that it appeared to be a crime of passion by a former lover. Later, she claimed it was the result of an intelligence operation to undermine and destabilise her government.

But his death helped accelerate the investigation and prompt Ms Kirchner’s successor as president, Mauricio Macri, to reverse Argentina’s rapprochement with Iran.

Last month, federal judge Julián Ercolini officially ruled that Nisman had been drugged, beaten and murdered, possibly by more than one person.

Mr Ercolini also charged Nisman’s former aide, Diego Lagomarsino, as an accessory to murder. Mr Lagomarsino was the last person in Nisman’s apartment and the bullet that killed the prosecutor had been fired by Mr Lagomarsino’s gun, the judge said.

Ms Kirchner, who became a senator after leaving the presidency, was indicted in December for treason as a result of the claims.

She launched an appeal earlier this month, arguing that the indictment was politically motivated.

The case is being closely watched in the United States where two members of the House of Representatives from Florida have introduced a resolution to Congress calling for a “full and just investigation” into Nisman’s death.

The resolution by Republican Florida representative Ileana Ros-Lehtinen and her counterpart Ted Deutch, a Democrat, said: “Alberto Nisman committed himself to uncovering the truth of the horrific AMIA bombing.”

“He refused to let Iran or Hezbollah get away with this act of terrorism, and he refused to let corrupt officials cover up the facts and wash their hands of this horrible attack.”