For years, Russia has promoted the Wagner mercenary group to authoritarian leaders in Africa as a force of fearsome warriors who could protect leaders’ grip on power and help their armies reclaim territories from armed groups.

In return, Moscow has gained access to resource-rich countries, dislodged Western and U.N. troops and seeded influence across West and Central Africa to a degree not seen since the fall of the Soviet Union.

But a major defeat for Wagner this summer in northern Mali showed that its actual capabilities might be overstated and unable to meet the ambitions of one of the group’s closest African partners. The New York Times confirmed the deaths of at least 46 Wagner fighters and 24 allied Malian soldiers by matching details seen in footage of the corpses, such as uniforms and tattoos, with imagery of the soldiers when they were alive.

The loss is Wagner’s largest ever on African soil and one of the deadliest in its entire history, outside Ukraine. Among those killed was Nikita Fedyanin, one of Wagner’s most influential online propagandists, whose death silenced a key platform for cultivating the group’s ruthless image. And the fallout extended to the Russian home front, too, The Times found, as relatives of the mercenaries accused Wagner of failing to tell them that their family members were dead.

Wagner’s combat experience in the region had rarely involved large complex offensives, and had never been in the remote mountains and desert of northern Mali where July’s battle took place. There they faced at least several hundred separatists largely from the Tuareg ethnic group, who are fighting for independence in the north. The separatists were later joined by Al Qaeda-affiliated Islamist militants, who occasionally partner with them against government forces.