Choguel Maiga, the former prime minister of Mali, was taken into custody on Wednesday after he was charged with embezzlement.
Maiga, 67, took office after a second coup in Mali in 2021 and led the civilian wing of the country's military junta until he was dismissed in November 2024.
The removal came days after he criticised the junta for postponing elections.
The charges follow a report from Mali's auditor general on the management of public funds while Maiga was prime minister.
A statement from the public prosecutor's office said the charges against Maiga involved money laundering equal to many billions of CFA francs, or several million euros.
No trial date has been set.
Maiga’s lawyer, Cheick Oumar Konare, told AFP news agency: “We believe in justice. We are calm while awaiting the trial."
Earlier this month, another former prime minister, Moussa Mara, was jailed after writing on social media that he supported jailed critics of the junta.
Last week, authorities in Mali said that a French national had been arrested on suspicion of working for the French intelligence services. Authorities also accused foreign states of trying to destabilise the country as they announced that dozens of soldiers had been detained for allegedly seeking to overthrow the government.
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'Covered by diplomatic conventions'
France's foreign ministry said the arrested employee was covered by the Vienna convention on consular relations, meaning he should be released.
The junta, led by President Assimi Goita, has turned away from Western partners, notably former colonial power France and other former allies and pivoted toward Russia.
In July, the country's military-appointed legislative body granted Goita a five-year presidential mandate, renewable as many times as necessary and without election.
Under the 41-year-old, Mali has slid into a security quagmire.
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The Malian army and its Russian allies have been tasked with fighting groups linked to Al-Qaeda and the Islamic State group, along with local criminal gangs. However, official forces are regularly accused of abuses against civilians.
Alongside Burkina Faso and Niger, which are also led by military juntas, Mali quit the Economic Community of West African States (Ecowas) earlier this year, accusing the regional bloc of being subservient to colonial ruler France.
The trio set up their own confederation called the Alliance of Sahel States.
(With newswires)
