The Death of Mali's former prime minister has been dubbed an "assassination" by Niger.

Former Mali Prime Minister Soumeylou Boubèye Maga was assassinated, according to Niger President Mohamed Bazoum.

Mr. Maga died in jail on Monday at a hospital in Bamako, the Malian capital, where he was receiving treatment.

He had been detained since August on suspicion of corruption.

As Maga's health denied his family's request for medical evacuation.

"[The former Malian prime minister's] death in prison is reminiscent of President Modibo Keita's death in 1977. I assumed such assassinations were a thing of the past "On Twitter, President Bazoum stated.

The president's reply may aggravate already fragile relations between the two countries.

President Bazoum "would have done well to minimize" his reaction, according to the privately-owned news website Actuniger.

In a statement, Mali's interim leaders expressed their sympathies to Maga's family, hailing him as a "great servant of the state."

Political parties have called for an investigation into the death of former Prime Minister Ibrahim Boubacar Keita, who was deposed by Mali's current military rulers.