MOSCOW (AP) — A Zambian student who had been serving a prison sentence in Russia and died fighting alongside Russian troops in Ukraine had been employed by Russian mercenary group Wagner, its leader said.

Wagner Group head Yevgeny Prigozhin said on the Russian social media app VKontake on Tuesday that the student, 23 year-old Lemekhane Nyireda, “died a hero.”

Zambian Foreign Minister Stanley Kakubo said earlier this month that Russian officials had informed the Zambian government of the death of Nyireda, who was a government-sponsored student before he was sentenced in Russia for unspecified crimes in April 2020.

He said the Zambian Embassy in the Russian capital of Moscow had established that Nyirenda died Sept. 22 and that his remains were transported to the Russian border town of Rostov ahead of repatriation to Zambia.

Before his prison sentence, Nyirenda was studying nuclear engineering at the Moscow Engineering Physics Institute. He was serving his approximately nine-year sentence at a prison on the outskirts of Moscow, according to the Zambian government.

Reports have circulated that Russia — desperate for more manpower to support what the Kremlin calls a “special military operation” in Ukraine — has offered freedom to convicts if they join the fight. Russia has employed the Wagner Group, whose head Prigozhin is said to be a close ally of President Vladimir Putin and has admitted meddling in U.S. elections — in several armed conflicts worldwide.

Prigozhin said he had asked the jailed student why he wanted to join the fight, given a high chance he would be killed, and that the Zambian citizen responded: “You Russians helped us Africans gain independence for many years. When it was difficult for us, you extended your hand to us and continue to do so now … The least I could do, probably, to pay our debts is go to war with you.”