The prosecutor's opinion flies in the face of the suicide hypothesis that has dominated the probe into Nisman's death in January 2015, days after he had accused the then president of covering up for Iran in the bombing of a Jewish center.
The arrest of the fugitives opens a new chapter in a political scandal that allegedly involves high level members of the government of former president Cristina Fernández de Kirchner in an ephedrine trafficking ring.
A new right wing president in Argentina and the gathering force of the opposition in Venezuela has left the longtime dominance of leftist governments in Latin America looking shaky.
Macri pledged to move the country away from the confrontational politics of outgoing president Cristina Fernández in an inauguration ceremony that came after two weeks of bitter bickering over the handover protocol.
Mauricio Macri's dramatic victory in Sunday's presidential runoff follows a dramatic life story marked by family wealth, a kidnapping, sporting titles, meditation and almost choking on a false mustache.
Macri’s win marks a major shake up of Argentine politics, putting an end to 12 years of Kirchnerismo. It also looks like a warning to several other leftist Latin American governments.
The weekend’s presidential elections to pick the successor of Cristina Fernández de Kirchner in Argentina see government-backed candidate Daniel Scioli only just beat the opposition's Mauricio Macri. A runoff will be held on November 22.
Although the top three candidates set themselves apart from the "intensity" of Kirchnerismo, they still share its political roots.
These days Pope Francis and President Fernández pose together smiling for the cameras. Things used to be very different.
Strangers embraced and tears were shed on the streets of Cuba's capital as word spread that decades of frosty relations with the United States would finally thaw.