Malian President Ibrahim Boubacar Keita and Prime Minister Boubou Cisse were on Tuesday arrested by the military in an apparent mutiny.
An army officer, Sidi Gakou, confirmed the incident to journalists in Bamako.
“The president and his prime minister have been arrested,” Gakou said by phone. “They are being taken to Kati military camp.”
The African Union Commission condemned the arrests and called for the immediate release of both leaders.
Earlier on Tuesday, the government had released a statement calling for calm, admitting that soldiers might have legitimate frustrations but they were prepared to engage in a dialogue.
Mali has been struggling to maintain stability since tens of thousands of opposition supporters accused Keita of gross intimidation and vote-buying during a parliamentary election in April, which gave his administration a firm majority.
Soldiers started to mutiny early Tuesday in the garrison town of Kati, 15 kilometres north-west of Bamako.
Gunfire was heard in the capital.