Video footage has shown trucks full of Wagner mercenaries smashing through barricades which had been hoped to slow their march on Moscow.
Group chief Yevgeny Prigozhin shocked the world last night when he announced he was launching an armed rebellion against his country's military leadership.
The column of Prigozhin’s armed force is heading north for a showdown with troops still-loyal to dictator Vladimir Putin amid rumours he has absconded from the capital.
Prigozhin and his troops are said to have already reached the key Russian city of Rostov-on-Don and could face a showdown with Russia’s forces by later this evening.
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Videos from the country show Prigozhin’s forces smashing through a pro-Putin barricade of trucks.
The approaching menace seems to have sparked panic among everyday residents.
Scores of terrified people were seen desperately trying to get out of Rostov aboard trains heading out of the city.
Other residents who remained in the city and attempted to block the streets were detained by Wagner fighters.
Mr Prigozhin said in a video on Friday: “He said in a social media rant: "PMC Wagner Commanders’ Council made a decision, the evil brought by the military leadership of the country must be stopped.
“They neglect the lives of soldiers. They forgot the word “justice”, and we will bring it back. “Those, who destroyed today our guys, who destroyed tens, tens of thousands of lives of Russian soldiers will be punished.
“I’m asking: no one resist. Everyone who will try to resist, we will consider them a danger and destroy them immediately, including any checkpoints on our way.
“And any aviation that we see above our heads. I’m asking everyone to remain calm, do not succumb to provocations, and remain in their houses.
“Ideally, those along our way, do not go outside. After we finished what we started, we will return to the frontline to protect our motherland.
In a sign of how seriously the Kremlin is taking the threat, security has been heightened in capital Moscow, Rostov-on-Don and other regions.
Wagner has lost many thousands of troops in bitter fighting and has complained regularly about the lack of support from Moscow.
The group is also suspected of having committed war crimes since the invasion on February 24 last year - and elsewhere in Africa.
Countries in the west, including the UK, US and Canada are keeping a close eye on the ongoing situation.
