"What happened in Niger is nothing other than the struggle of the people of Niger with their colonizers," Prigozhin said.
Also targeted in Monday's action was Mali’s Chief of Staff of the Air Force, Alou Boi Diarra, and Malian Air Force Deputy Chief of Staff, Adama Bagayoko.
The seemingly chaotic call-up process triggered rare public criticism, and drove hundreds of thousands to flee Russia to avoid being sent to fight.
"Information obtained shows that during a training flight by US soldiers, contact with the drone was lost and it then fell into a forest area," the defense ministry wrote.
"Training or joint exercises of the Belarusian army and the Wagner Group is undoubtedly a provocation," Zbigniew Hoffmann told PAP.
"Wherever Wagner operates, it has a catastrophic effect on communities," Britain's minister for Development and Africa Andrew Mitchell said.
"The armed forces of Belarus continue joint training with the fighters of the Wagner PMC (Private Military Company)," the Belarusian defense ministry said.