Russia's Defense Ministry says Wagner mercenaries are marching on Moscow. Wagner head Yevgeny Prigozhin has been formally charged with "inciting an armed revolt" by Russia's Federal Security Bureau.

Yevgeny Prigozhin, owner of the Wagner private military contractor, made his most direct challenge to the Kremlin yet on Friday, calling for a rebellion aimed at ousting Russia's defense minister.

Catch up on key developments and the latest in-depth coverage of Russia's invasion of Ukraine.

Yevgeny Prigozhin, known as "Putin's Chef" because of his company's origins in the catering business, now fields a mercenary army of 50,000. Its role in Ukraine is central to Russia's war effort.