Russian Wagner mercenaries were "moving across" the Lipetsk region some 400 kilometres (250 miles) south of Moscow, the governor said Saturday, en route to Moscow after vowing to overthrow Russia's military leadership.
Their chief Yevgeny Prigozhin has vowed to make it to Moscow, after moving his men from occupied Ukraine into Russia overnight and launching an armed insurrection against Russia's top brass.
Wagner mercenaries have occupied an army HQ in the southern city of Rostov-on-Don and were reportedly in the Voronezh region.
But the Lipetsk region is so far the closest location to Moscow where Wagner columns have been spotted.
"Hardware of the Wagner mercenary group is moving across the territory of the Lipetsk region," Governor Igor Artamonov said on Telegram.
"I remind you that residents are strongly recommended not to leave their houses or to make trips on any mode of transport."
He did not say exactly where in the region the Wagner fighters were seen.
The pro-Kremlin Telegram channel Rybar, which closely analysed the conflict in Ukraine, has said that Wagner columns were seen near Yelets, 390 kilometres (240 miles) south of Moscow.
AFP was not able to verify the report.
Further north closer to Moscow, the Kaluga region introduced travel restrictions as Wagner forces marched on the capital.
"Please refrain from travelling by private vehicle on these roads unless absolutely necessary," Governor Vladislav Shapsha said in a statement on social media, referring to transport arteries between his region and several others, including those bordering Ukraine.
Russia has introduced a "counter-terror regime" in Moscow.
In the southern Voronezh region, authorities said the military was carrying out "combat" operations and said a huge oil depot was on fire.
President Vladimir Putin has vowed to punish the mutineers, calling them "traitors".
Prigozhin fired back at the long-time leader, saying he was "deeply mistaken", and vowed to press onto Moscow.
He said his men entered Russia and occupied the army building in Rostov-on-Don without firing a "single shot", claiming to have support from locals.
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