Intelligence officials conducted briefings on potential for unrest in nuclear-armed country a full day before it unfolded, the Washington Post and New York Times report

A serviceman stands atop of an armored vehicle of the Wagner Group military company, as he guards an area at the HQ of the Southern Military District in a street in Rostov-on-Don, Russia, Saturday, June 24, 2023. (AP)

WASHINGTON — US spy agencies picked up signs days ago that mercenary chief Yevgeny Prigozhin was preparing to rise up against Russia’s defense establishment, US media reported on Saturday.

Intelligence officials conducted briefings at the White House, the Pentagon and on Capitol Hill about the potential for unrest in nuclear-armed Russia a full day before it unfolded, the Washington Post and New York Times reported.

Spy agencies first began tracking indications that Prigozhin and his Wagner mercenary force intended to move against the Russian military leadership in mid-June, the Post said.

The Times said the information was both solid and alarming by mid-week, leading to the flurry of briefings.

In an uprising that played out with dizzying speed, Prigozhin’s forces moved from their camps in Ukraine into Russia Friday and took over a regional military command in the southern city of Rostov-on-Don, before advancing toward Moscow.

Just as suddenly, the advance was called off on Saturday, and Russian state media said the Wagner troops would return to Ukraine while Prigozhin would flee to neighboring Belarus.

In this handout photo taken from video released by Prigozhin Press Service, Yevgeny Prigozhin, the owner of the Wagner Group military company, records his video addresses in Rostov-on-Don, Russia, Saturday, June 24, 2023. (Prigozhin Press Service via AP)

The Kremlin said it would not prosecute Prigozhin or the armed members of the Wagner group who participated in the march.

As US intelligence officials pinned down information that Prigozhin was preparing military action, they grew concerned about chaos in a country with a powerful nuclear arsenal, the Times reported.

US spy agencies believe that Putin himself was informed that Prigozhin, once a close ally, was plotting his rebellion at least a day before it occurred, the Post reported.

Prigozhin had been locked in a bitter months-long power struggle with the defense ministry as his ragtag forces spearheaded the costly battles for limited gains in eastern Ukraine.

He had earlier accused the Russian military of trying to “steal” victories from Wagner and slammed Moscow’s “monstrous bureaucracy” for grinding progress on the ground.

And he directly blamed Russian Defense Minister Sergei Shoigu and other senior officials for his fighters’ deaths, claiming Moscow had not provided sufficient ammunition.

Unlike Russia’s generals, who have been criticised for shirking the battles, the stocky and bald Prigozhin regularly poses for pictures alongside mercenaries allegedly on the front lines.

A man poses for a photo with members of Wagner group in a street in the city of Rostov-on-Don on June 24, 2023. (Roman ROMOKHOV / AFP)

Earlier this year he posted on social media a picture from the cockpit of a SU-24 fighter jet and challenged Ukrainian President Volodymyr Zelensky to an aerial duel.

Prigozhin was sanctioned by Washington which accused him of playing a role in meddling in the 2016 US presidential election, in particular through his internet “troll factory.”

He at the time denied any involvement and in 2020 asked for $50 billion in compensation from the United States.

In July 2018, three journalists researching Wagner’s operations in the Central African Republic for an investigative media outlet were killed in an ambush.

Western countries have accused the private fighting group of coming to the aid of the military junta in Mali, in a move that contributed to France’s decision to end an almost decade-long military operation there.

As reported by The Times of Israel