Insecurity has grown in the West African country since Islamist insurgents who took root in its arid north a decade ago escalated attacks and seized territory.
Action in Africa is increasingly becoming part of the broader tensions between Moscow and the West.
A bus was attacked by unidentified gunmen as it traveled its twice-weekly route from the village of Songho to a market in Bandiagara.
Theoneste Bagosora was serving a 35-year sentence after being found guilty of crimes against humanity by the then International Criminal Tribunal for Rwanda (ICTR)
President Bah Ndaw, Prime Minister Moctar Ouane & defense minister Souleymane Doucoure were all taken to a military base in Kati outside the capital Bamako, the sources said.
"The attack started with mortar fire, followed by an attempted car bomb and then a direct attack," a UN spokeswoman said.
"A historic figure of the jihadist movement in the Sahel, Bah ag Moussa is considered responsible for several attacks against Malian and international forces," Parly said in a statement.
Toure's life, in many ways, symbolized the stop-start nature of democracy in the West African country.