news.sky.com/story/ukraine-war-what-is-the-wagner-group-of-secret-russian-mercenaries-12562034?dcmp=snt-sf-twitter
The group is believed to be funded by Yevgeny Prigozhin, a businessman with close links to Vladimir Putin who is also alleged to run Russia's "troll farm", the Internet Research Agency.
And
The European Union said Wagner was founded by Dmitry Utkin - a former Russian soldier reportedly adorned with Nazi tattoos.
It is said to have been named after Richard Wagner, Hitler's favourite composer.
The Wagner Group is privately owned but its management and operations are "deeply intertwined" with the Russian military and intelligence community, according to the Center for Strategic and International Studies (CSIS), an American think tank.
The Russian armed forces reportedly provide the group with munitions and transport aircraft, and the head of Ukraine's security services has described it as a "private army of Putin".
The company has at least 6,000 employees and is said to be registered in Argentina, with offices in Saint Petersburg and Hong Kong.
Valery Zakharov, a former member of the Russian state security service, is "a key figure in the Wagner Group's command structure and keeps close links with the Russian authorities", according to the EU.
The Russian government denies any involvement with the group and insists it does not legally exist because private military contractors are not legal in Russia
And
The Wagner Group is said to be used by the Russian government in conflicts where plausible deniability is called for.
The use of these mercenaries - described as "ghost soldiers" - also allows Russia more secrecy about its military operations abroad and the number of losses.
Some believe that the organisation does not actually exist as a private company but is in reality a hidden branch of the Russian Ministry of Defence that reports to the Russian government.
Private security companies and private military companies are essentially "freelance soldiers" who can be hired cheaply and are more efficient than a regular military force because a small number of them can be deployed for a targeted operation, according to CSIS.
Article also says how 400 operatives from Wagner were sent to Kyiv to kill Zelensky.