Russia was earlier on Saturday thrown into a state of fear and confusion after Wagner militia chief Yevgney Prigozhin initiated a military rebellion against President Vladimir Putin and his regime.

Yevgeny Prigozhin has called for a rebellion against the army, but has denied plotting a coup.

The head of the private military contractor maintains his forces are on a “march for justice” to remove corrupt and incompetent commanders he holds responsible for the botched Ukrainian war.

Wagner claims that it has conquered the Russian city of Rostov-on-Don, near the Ukrainian border, and that inhabitants have been ordered to remain indoors, according to BBC News.

The group also hinted that it has taken control of military facilities in Voronezh, which is located halfway between Rostov and Moscow.

While responding to the development, Putin addressed the Russians on Saturday, saying that the Wagner leader had ‘stabbed him in the back,’ as Moscow is on lockdown as troops dig in to defend the capital.

President Putin promised to crack down on an armed mutiny he compared to Russia’s Civil War a century ago.

In a televised address from the Kremlin, Putin said Russia’s very existence was under threat, Reuters reported.

“We are fighting for the lives and security of our people, for our sovereignty and independence, for the right to remain Russia, a state with a thousand-year history,” he said.

“All those who deliberately stepped on the path of betrayal, who prepared an armed insurrection, who took the path of blackmail and terrorist methods, will suffer inevitable punishment, will answer both to the law and to our people.”

Meanwhile, Western capitals have expressed concern about happenings in the nuclear-armed Russia. The White House said President Joe Biden was briefed.

“This represents the most significant challenge to the Russian state in recent times,” Britain’s defence ministry said.