Yevgeny Prigozhin, the head of the Russian mercenary outfit Wagner Group, said the Russian army attacked his troops on Friday.
"We were ready to make concessions to the defense ministry, surrender our weapons," Prigozhin said in an audio message released by his representatives. "Today, seeing that we have not been broken, they conducted missile strikes at our rear camps."
The Wagner head said the "evil" of the Russian leadership must be stopped.
"Those who destroyed our lads, who destroyed the lives of many tens of thousands of Russian soldiers, will be punished. I ask that no one other resistance," Prigozhin said.
"There are 25,000 of us and we are going to figure out why chaos is happening in the country," he added.
The Wagner chief said he was carrying out a march for "justice" in retaliation against Russian military leadership, rather than a "coup."
But Russia's state security agency, the FSB, launched an investigation into Prigozhin for what they said amounted to "mutiny"
The alleged attack on Wagner forces came just hours after Prigozhin lashed out at Russian military leaders, saying they deceived President Vladimir Putin into launching the invasion of Ukraine.
The Russian Defense Ministry denied Prigozhin's claims of an attack, saying the Wagner head's allegations "do not correspond to reality and are an informational provocation."
Prigozhin: Ukraine invasion was to benefit military leaders
In a video released on Telegram earlier Friday, Prigozhin made fiery remarks which criticize Russia's rationale for commencing the assault on Ukraine, which began on February 24 of last year.
Prigozhin alleged that the Russian Defense Ministry "is trying to deceive society and the president and tell us how there was crazy aggression from Ukraine and that they were planning to attack us with the whole of NATO."
The Wagner chief referred to the official Kremlin justification for the war as a "beautiful narrative."
"The special operation was started for a different reason," Prigozhin said, referring to the Russian government's preferred term for the invasion.
Prigozhin claimed that the assault on Ukraine was launched so that Russian Defense Minister Sergei Shoigu could become a marshal and receive military accolades. The rank of marshal is the highest in the Russian military, with only one former minister of defense having received the title so far.
Contrary to Moscow's claims, Prigozhin also said the war wasn't needed to "demilitarize or denazify Ukraine."
Putin has said that Russia's assault on its neighbor was necessary to purge "Nazis" from the country's leadership, an attempt to appeal to Russia's historical pride over defeating Nazi Germany in World War II. Yet, the argument runs contrary to the fact that Ukrainian President Volodymyr Zelenskky is Jewish, with the Ukrainian leader having lost family due to the Holocaust.
The Wagner chief said the invasion was an attempt to acquire "material assets" to divide among Russian elites.
Wagner chief refrains from criticizing Putin
Despite Prigozhin's attacks on Russia's military leadership, he didn't explicitly criticize Putin. The Wagner chief is still reliant on Putin's support and maintains a close relationship with the president.
Some analysts say Prigozhin may be trying to win approval from the public amid setbacks in Ukraine.
"He is posturing as an enemy of the elites, even though he is a product of Putin's system, the embodiment of his regime and state contracts," Andrei Kolesnikov of the Carnegie Russia Eurasia Center told the Associated Press news agency.
"Prigozhin is playing an independent politician, raising the stakes and testing the system's limits," Kolesnikov added. "But it's only technically possible for as long as Putin finds him useful and is amused by his escapades."
The Wagner chief has been referred to as "Putin's chef" after he earlier ran a catering service that worked for the Kremlin. Prigozhin now maintains a global influence, with Wagner mercenaries involved not only in Ukraine but also in African countries such as Mali.
wd/rs (Reuters, AP, AFP, dpa)