According to reports circulating on social media, Mangushev was shot in the head at close range, execution-style, at a checkpoint in the Russian-occupied part of Luhansk Oblast.
Mangushev (call sign "Bereg") was sent to the neurosurgery department of one of the hospitals in Kadiivka (which the Russians call Stakhanov) with a gunshot wound.
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"So, performing with someone else's skull has brought (Mangushev) misfortune," Kazanskyi wrote.
"Mangushev got shot through his own skull. He is still alive, but with such an injury, the prospects are not very good."
According to the journalist, "karma caught up" with Mangushev, and it was soldiers of Chechen warlord Ramzan Kadyrov who most likely shot the Russian mercenary.
"The details are still uncertain, but they say there is a reason to shout 'Akhmat-sila!'" Kazanskyi said, quoting what Mangushev's attackers are reported to have cried during the shooting.
Russian sources also confirmed that an "accident" happened to the mercenary. Russian authorities declined to release more information about the attack, but Russian milbloggers condemned the attack and speculated that Mangushev may have been on his knees and shot from behind.
"Information from the doctors: it was made from a short-barreled weapon, a bullet of approximately 9 mm, close-up, occipital-parietal region, wound channel from the back down at 45 degrees," the Russians quoted one of the invaders who fought in the same unit as Bereg.
Mangushev is the leader of the neo-Nazi movement "Light Rus". He is also considered the creator of PMC "Raccoon", which closely cooperated with Russia's FSB security service.
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The U.S. think tank Institute for the Study of War (ISW), quoting a Western expert, noted that Mangushev has ties to Wagner Group and that an attack against Mangushev may have been a message to the Wagner Group and its financier, Yevgeny Prigozhin.
During his shameful "skull brandishing" speech in the summer of 2022, Mangushev repeated the stereotypes of Russian propaganda and called for the genocide of Ukrainians.
The propagandist stated that the Russian Federation "is not at war with people, but with the idea" of Ukraine's existence, and "all bearers of this idea must be destroyed."