The owner of the Wagner private military group, Yevgeny Prigozhin, said early Saturday that his forces had crossed from Ukraine into Russia and entered the city of Rostov facing no resistance by border guards. Prigozhin said his men were ready to go “all the way” against the Russian military and would destroy anyone who stood in their way.

In an audio recording posted on the Telegram messaging app, the Wagner chief said young conscripts at checkpoints stood back and did not fight, adding that his forces “aren’t fighting against children.”

Prigozhin said Friday that Wagner field camps were struck by rockets, helicopter gunships and artillery fire on orders from the chief of the military’s General Staff, General Valery Gerasimov. He charged that Gerasimov issued the order after a meeting with Defense Minister Sergei Shoigu, at which they decided to destroy Wagner.

The Russian Defense Ministry rejected Prigozhin’s claims.

Russia’s Federal Security Services (FSB) opened a criminal investigation on Friday against Prigozhin, accusing him of armed mutiny, citing the National Anti-Terrorism Committee (NAC), an arm of the FSB.

The crime is punishable by up to 20 years in prison, according to Russia’s chief prosecutor.

Russian President Vladimir Putin is getting round-the-clock updates from all relevant state security agencies on actions taken to thwart the attempted armed mutiny, the TASS news agency reported Saturday.

Military vehicles have been seen on Moscow streets, Reuters reported.

The White House is monitoring the standoff between top Russian military officials and the Wagner force and will be consulting with allies and partners on developments, National Security Council spokesperson Adam Hodge said Friday.

The NAC insisted there is no basis to the allegations made by Prigozhin that the Russian Ministry of Defense conducted airstrikes against Wagner bases, killing 2,000 of his fighters.

Prigozhin said the Wagner Group commanders’ council has vowed to punish Shoigu.

“The evil that the military leadership of the country is responsible for must be stopped. They neglect the lives of soldiers, they forgot the word ‘justice,’ which we will bring back,” he said.

“Therefore, those who killed our guys today, those who killed tens, many tens of thousands of lives of Russian soldiers, will be punished,” he said, announcing that his forces would march to secure justice for the lost fighters.

General Sergei Surovikin, the deputy commander of Russian forces in Ukraine, appealed to Wagner’s leaders, commanders and fighters.

“Together with you we have passed a difficult, hard way, we have fought together, taken the risks, suffered losses, we have won together. We are the same blood, we are warriors,” he said. :I call you to stop. The enemy is only waiting for our domestic political situation to deteriorate. We must not play into the hands of the enemy at this difficult time for the country.”

According to TASS, the FSB is calling on Wagner fighters “not to follow Prigozhin’s criminal orders” and to detain him.

Early Saturday, according to audio posted on Telegram, Prigozhin said he and his men had crossed into Russia without resistance.

“Everyone who will try to put up resistance … we will consider it a threat and destroy it immediately, including any checkpoints that will be in our way and any aircraft that we see over our heads. I am asking everyone to remain calm and not succumb to provocations, stay in their homes. It is advisable not to go outside along the route of our movement,” he continued.

“After we finish what we started, we will return to the front to defend our Motherland,” Prigozhin said. “There are 25,000 of us, and we are going to figure out why this country is in such a mess. Twenty-five thousand are expected as a tactical reserve, and the strategic reserve is the whole army and the whole country. Everyone who wants to join. We must end this disgrace,” he said.

Earlier Friday, Prigozhin said the Kremlin’s reasoning for invading Ukraine is based on lies fabricated by the army’s top brass. Prigozhin has for months openly accused Shoigu and Gerasimov of gross incompetence.

“The Defense Ministry is trying to deceive society and the president and tell us a story about how there was crazy aggression from Ukraine and that they were planning to attack us with the whole of NATO,” Prigozhin said in a video clip released on Telegram by his press service.

He went on to accuse Shoigu: ”The war was needed … so that Shoigu could become a marshal … so that he could get a second ‘Hero’ [of Russia] medal,” he added. ”The war wasn’t needed to demilitarize or denazify Ukraine.”

The Wagner chief also attacked the ruling elite, saying greed fueled its desire to absorb the assets from Ukraine’s Donbas region. ”The task was to divide material assets,” he said. “There was massive theft in the Donbas, but they wanted more.”

Some information for this story came from The Associated Press, Agence France-Presse and Reuters.