The planes started moving in late December and early January.

Onboard the secretive military aircraft from Libya were hundreds of hardened mercenaries of the Wagner Group, the shadowy umbrella of private military contractor firms linked to Vladimir Putin’s ally Yevgeny Prigozhin. Their destination was the same place where the so-called “little green men” first came to international prominence in 2014: Ukraine.

Experts closely following the movements and actions of the Wagner complex for years say the military contractors – who include former and active-duty Russian, Ukrainian, Belarusian and Serbian soldiers – have been on the ground in Ukraine for months, their presence confirmed in news reports and hinted at in cryptic social media posts by accounts associated with the mercenary group.

But many questions remain about their role in the Ukraine conflict.

“They are skilled at counterinsurgency, and Ukraine is the birthplace of the group,” said Ruslan Trad, a specialist on the Wagner Group who has traced its movements in the Middle East and Africa.

I was interviewed for The Independent on the possible role of Wagner mercenaries in Ukraine and what are my doubts about the recent media reports linked to the group: