Wagner's founder Yevgeny Prigozhin in an audio message on Friday claimed his forces would now punish Russia's defense minister and chief of general staff, telling other units to stand down and not offer resistance.
"There are 25,000 of us and we are coming to sort things out. ... Those who want to join us, it's time to finish with this mess," Prigozhin said.
Prigozhin also accused defense minister Sergey Shoigu of "cowardly fleeing" from Rostov in southern Russia and ordering an attack on Wagner forces.
Prigozhin published a shaky video on Friday that showed a shattered group of trees and a burning trench, claiming it was a Wagner camp shelled by Russian troops and alleging many Wagner troops were killed.
Russia's defense ministry has already denounced the video, calling it an "information provocation."
A Kremlin spokesperson said Russian President Vladimir Putin is aware of the video.
"President Putin has been informed of all the events around Prigozhin. Necessary measures are being taken," the spokesperson said.
Russia's FSB has issued a statement accusing Prigohzin of calling for "the start of an armed civil conflict" in Russia.
The FSB called on Wagner fighters not to follow Prigozhin's orders and to assist in his arrest.
Prigozhin has denied this is a "military coup" calling it a "march for justice."
"They neglect the lives of soldiers, they forgot the word 'justice,' and we will return it," Prigozhin said in the video. "Therefore, those who destroyed our guys today, and tens of thousands of lives of Russian soldiers, will be punished."
White House National Security Council spokesperson Adam Hodge, released a statement that said the counsel is "monitoring the situation and will be consulting with allies and partners on these developments." Hodge also confirmed later in the evening on Friday that President Joe Biden had been briefed.
Gen. Sergey Surovikin, a senior Russian general who has been linked with Prigozhin, gave a video address calling on Wagner fighters to stop their rebellion and turn back.
Surovikin was appointed the top commander of Russia's 'special military operation' in Ukraine between last September and January. He was removed in January and replaced by Russia's chief of the general staff Valery Gerasimov, whom Prigozhin is trying to topple.
This comes hours after Prigozhin launched an extraordinary verbal attack on Russia's military leadership, and saying the invasion of Ukraine was based on lies.
Wagner chief says Russian invasion based on lies
The head of Russia's Wagner mercenary group, Yevgeny Prigozhin, said the Kremlin's justifications for its invasion of Ukraine are based on lies, in another extraordinary attack on the country's military and political leadership.
Prigozhin, a key ally of Putin, in a video posted Friday, contradicted the public explanations for the war, including the central claim made by Putin that the 2022 invasion was necessary to prevent an attack from Ukraine.
Since launching the war, Putin has painted it as a defensive operation to protect Russia. He's claimed it was needed to stop imminent large-scale attacks from Ukraine on largely Russian-speaking eastern regions in Donbas that Russia has occupied since 2014.
But in his video address, Prigozhin, whose fighters have played a leading role in the war, said that was not true and there had been no imminent risk of attack from Ukraine.
"The ministry of defense now is trying to deceive society, the president, and tell a story there was insane aggression from Ukraine and that they intended to attack us with the whole NATO bloc," Prigozhin said.
"The Special Military Operation that began on Feb. 24 was started for completely different reasons," he said.
Prigozhin has been in a public feud with Russia's defense ministry and its head Sergey Shoigu for months, blaming them for Russia's disastrous prosecution of the war. As Russia has faced deepening setbacks in Ukraine, he has become an unexpected, prominent critic of Russia's leadership, using social media to post almost daily video updates excoriating it as incompetent, but stopping short of directly criticizing Putin.
Prigozhin also said in Friday's video that the two goals Putin announced at the start of the war— the "demilitarization" and "de-Nazification" of Ukraine—were "pretty stories."
Instead, he blamed Shoigu, the defense ministry and a "clan of oligarchs" for starting the war. He accused Shoigu of seeking glory and wanting "to rob" Ukraine and divide up its assets.
Prigozhin's attacks are extraordinary in Russia, where public criticism of the authorities risks harsh punishment. Since the war began last year, criticism of the military leadership has become a criminal offense.
That has led to speculation among experts about why Prigozhin is enjoying such license. Some observers have suggested Prigozhin might be speaking with the tacit approval of the Kremlin, which may be looking to shift blame for the war from Putin by scapegoating other figures such as Shoigu.
Prigozhin did not directly attack Putin in the video, instead claiming the president was being deceived by his generals and other figures around him. In reality though, Putin—not Shoigu—has taken the lead in making the claims around Donbas and de-Nazification the central justifications of the war, reciting them in his speech declaring his "Special Military Operation."
The implicit picture Prigozhin gave of Putin as weak and out of touch was also remarkable, implying he was manipulated by a clan of wealthy businessmen around him and lied to by his military. The war, as described by Prigozhin, was not about protecting Russia or resisting NATO expansion, but instead greed.
"The war was needed by oligarchs," Prigozhin said. "It was needed by that clan that today practically rule Russia." He added Russia's "sacred war" had "turned into a racket."
Prigozhin lambasted Russia's military leadership for the huge casualties its troops have suffered. He accused Shoigu of hollowing out the armed forces under Putin through corruption and cronyism, crippling its ability to fight effectively and then catastrophically botching the invasion after believing it would be an easy victory.
"There is a total absence of management," Prigozhin said, calling Shoigu a "weak grandfather."
"Someone should answer for the lives of those soldiers," Prigozhin said in Friday's video.
Prigozhin this week has accused the defense ministry of once again presenting a falsely upbeat picture of how Russia is fending off Ukraine's ongoing counteroffensive in southern Ukraine. Russia's military has claimed to have largely stymied the counteroffensive and inflicted heavy losses on Ukraine.
Putin himself has trumpeted those alleged successes, repeating claims Ukraine has suffered heavy losses of Western equipment.
But Prigozhin has said in Russia's position is far more difficult, as Ukraine presses attacks at two points on the Zaporizhzhia front in the south, and Moscow is at risk of another significant defeat.
"On the ground now, today, the Russian army is retreating on the Zaporizhzhia and Kherson regions," Prigozhin said in Friday's video. He added that Ukrainian forces were advancing "deeper and deeper and deeper into our defenses" around Bakhmut, which his Wagner forces helped capture weeks ago.
"The leadership of the ministry of defense is thoroughly deceiving the president, and the president is receiving reports that don't correspond with reality in any way," Prigozhin said.
"Two agendas are forming—one on the ground, the other on the president's table," he said.
ABC News' Ben Gittleson contributed to this report