• Residents of Moscow have been ordered to stay home on Monday.
• Mayor Sergey Sobyanin said authorities are on "high alert" as Wagner force approach the capital.
• Sobyanin urged residents to stay home "as much as possible."

Residents of Moscow are being urged to remain indoors and stay home from work on Monday following reports that heavily-armed mercenaries loyal to Yevgeny Prigozhin are just hours from the city.

In a message posted on Telegram, Moscow Mayor Sergey Sobyanin announced that he had ordered Monday a "non-working day" — with an exception for security services and other authorities — amid what he termed a "counter-terrorist operation."

"I ask you to refrain from traveling around the city as much as possible," Sobyanin wrote. Authorities are on "high alert," he added, describing the situation in Moscow as "difficult."

The stay-home order comes after Prigozhin's Wagner mercenary group appeared to seize control of Rostov-on-Don, a port city of more than one million people, earlier on Saturday. The apparently bloodless capture of the city was followed by reports that Wagner forces are marching toward Moscow.

Video posted to social media later on Saturday appeared to show an oil depot in Voronezh, about halfway to the capital, on fire after an attack from a military helicopter.

Wagner forces then made it to the region of Lipetsk, according to the local governor, just a few hours' drive from the capital. Large swaths of the main road between the region and Moscow, the M4 highway, are now closed, according to Google Maps, with photos on social media appearing to show construction equipment tearing up portions of the roadway to obstruct Wagner's progress.

Prigozhin, who claims to control a force of some 25,0000 men, has said he is leading a "march for justice," the culmination of a months-long feud with Russian military authorities who he accuses of undermining the war in Ukraine. In an address early on Saturday, Russian President Vladimir Putin accused Prigozhin — formerly a close ally — of treason.

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