In a speech on Saturday, Russian President Vladimir Putin vowed to suppress an armed rebellion led by mercenary chief Yevgeny Prigozhin, who claims to have taken control of a southern city to remove the military leadership.
In Washington, officials said President Joseph R. Biden had been briefed on the evolving situation.
Putin said that Yevgeny Prigozhin, the head of the paramilitary Wagner group that seized the southern Russian city of Rostov, had committed treason and must be crushed.
Putin denounced the mutiny as treason and a betrayal of Russia, promising harsh consequences for those involved.
Prigozhin had accused Defence Minister Sergei Shoigu and General Valery Gerasimov of incompetence and alleged that the military had killed numerous members of his private militia, Wagner, in an airstrike.
The details of the situation remain unclear, but Prigozhin’s actions mark a significant domestic crisis for Putin since the invasion of Ukraine.
Videos circulated online on Friday night, the time in Washington DC showed troops around Restov entering a building.
Security measures have been increased in Moscow.