MOSCOW, June 24, 2023 (BSS/AFP) - A Russian state news agency on Saturday reported that Moscow authorities had instituted tighter security measures after the head of the Wagner mercenary group called for the ouster of Russia's military leadership.

"Security measures in Moscow have been tightened. All critical facilities, government and transport infrastructure objects have been put under reinforced protection," the TASS state-run news agency reported, citing a law enforcement source.

The report came after Yevgeny Prigozhin, Wagner's founder, accused Moscow of targeting his forces with deadly missile strikes and vowed to retaliate.

The 62-year-old, whose forces have played a central role in key battles in east Ukraine, said he was launching a march to restore "justice," calling for change at the top of the defence ministry.

Russian state television meanwhile broadcast an unscheduled special report, echoing statements from the FSB security service, which accused Prigozhin of fomenting a "civil conflict" and urged Wagner fighters to detain him.

Local media published amateur footage showing armoured vehicles deploying throughout the capital, including near the defence ministry.