Many thought that Vladimir Putin's invasion of Ukraine on 24 February was going to be a quick 'takeover' job.
Six months on, the war hasn't stopped and neither side plans on folding any time soon.
In and amongst it has been the Wagner Group, a mercenary unit which was originally deployed to conflicts in Syria and Libya.
Its alleged crimes have ranged from committing rapes and robberies against civilians in the Central African Republic, to planting explosive devices in and around the Libyan capital, Tripoli.
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The secretive group was part of an investigation by the BBC, that claims that 51-year-old former Russian army officer, Dmitry Utkin, is the founder.
The group's first reported outing was during Russia's annexation of Crimea in 2014.
In 2015, the Wagner Group then allegedly started operating in Syria.
Also in 2017, it was reported that the group was brought in to defend diamond and coal mines in Central African Republic and Sudan, respectively.
And now the group has allegedly been fighting alongside the Russian army in Ukraine, while allegedly recruiting criminals to join battle.
Russia has denied any involvement because the group 'officially' does not exist.
Tracey German, professor of conflict and security at King's College London, said: "About 1,000 of its mercenaries supported the pro-Russian militias fighting for control of the Luhansk and Donetsk regions.
"Its mercenaries are thought to be some of the 'little green men' who occupied the region.
"Running a mercenary army is against the Russian constitution.
"However, Wagner provides the government with a force which is deniable.
"Wagner can get involved abroad and the Kremlin can say, 'It has nothing to do with us'."
An alleged ex-fighter told the publication: "It is a structure, aimed at promoting the interests of the state beyond our country's borders."
Andrey Chuprygin, an expert working with the Russia International Council, claims the Russian government 'let them join this thing, and we'll see what the result is'.
Sorcha MacLeod, chair of the United Nations Working Group on the use of mercenaries, said the group 'operates in a situation of opacity, there’s a real lack of transparency and that’s the whole point'.
"Their whole structure of the group basically allows them to keep a 'distance between the Russian state and the group," she said.
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Anish Vij