By Andrew Osborn and Kevin Liffey

LONDON Russian mercenary chief Yevgeny Prigozhin on Friday accused the Russian military of "destroying" his fighters, without fully explaining his accusation, and vowed to stop the "evil" of the military leadership.

The Defence Ministry quickly issued a statement saying Prigozhin's accusations "are not true and are an informational provocation".

In a series of audio messages on his official Telegram channel, Prigozhin said:

"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 offer resistance."

He said details of what had occurred were just emerging, but added: "The Minister of Defence arrived specially in Rostov to carry out an operation to destroy the Wagner PMC (private military company)."

An unverified video posted on the "Razgruzka Wagner" (Wagner's Combat Vest) Telegram channel showed a scene in a forest where small fires were burning and trees appeared to have been broken by force.

It carried the caption: "A missile attack was launched on the camps of PMC Wagner. Many victims. According to eyewitnesses, the strike was delivered from the rear, that is, it was delivered by the military of the Russian Ministry of Defence."

Prigozhin vowed to avenge the incident: "There are 25,000 of us and we are going to figure out why chaos is happening in the country."

But he also added: "This is not a military coup."

Earlier in the day, Prigozhin, appeared to cross a new line in his increasingly vitriolic feud with Moscow, saying that the Kremlin's rationale for invading Ukraine was based on lies concocted by the army's top brass.

Prigozhin, whose frequent tirades on social media belie his limited role in the war as head of the Wagner private military company, has for months been openly accusing Defence Minister Sergei Shoigu and Russia's top general, Valery Gerasimov, of rank incompetence.

But on Friday he for the first time dismissed Russia's core justifications for invading Ukraine on Feb. 24 last year in what it calls a "special military operation".

"The war was needed ... so that [Defence Minister Sergei] Shoigu could become a marshal ... so that he could get a second 'Hero' [of Russia] medal," Prigozhin said in another audio message. "The war wasn't needed to demilitarise or denazify Ukraine."

(Reporting by Reuters; Writing by Kevin Liffey; Editing by Daniel Walis)