“At the beginning of this week, one of the Chechen units was shelled in the Kherson region,” Kadyrov, a prominent ally of Russian President Vladimir Putin and the ruler of the Chechen Republic, said on Telegram late on Thursday.
“Twenty-three fighters have died and 58 have been injured.”
The Kremlin ally rarely reveals defeats but admitted that losses among his fighters, who are supporting Russia, were “big on that day”.
Ukrainian sources had reported earlier this week that a Chechen unit in the southern Ukrainian region of Kherson had given away its location via photos on social networks, which led to it being hit by artillery fire.
Kadyrov’s comments were unusual given that pro-Moscow forces have rarely admitted to major battlefield losses, and Russian officials do not publish figures on their own casualties.
The Chechen leader also called on his compatriots to be mobilised for the war in Ukraine.
Since the beginning of the Russian war more than eight months ago, Kadyrov has distinguished himself as one of the fiercest supporters of the conflict and has also sent his own units into Ukraine.
But he has regularly criticised the Russian army leadership – often in conjunction with the financier of the mercenary Wagner units, Yevgeny Prigozhin, for being too soft. Kadyrov has also called for the use of nuclear weapons against Ukraine.
Meanwhile, Ukrainian President Volodymyr Zelenskyy compared his country’s fight against Russia with the Nazi resistance in World War II, saying Moscow is pursuing the same goals as Nazism once did.
“The form of evil has changed, but the essence is unchanged,” Zelenskyy said in a video message broadcast in Kyiv on Thursday night.
Russia, he said, had gone from neighbour to aggressor to terrorist – and was guilty of war crimes.