"CNN has tracked Wagner mercenaries in the Central African Republic, Sudan, Libya, Mozambique, Ukraine and Syria. Over the years they have developed a particularly gruesome reputation and have been linked to various human rights abuses."

https://www.google.com/amp/s/amp.cnn.com/cnn/2023/06/23/europe/wagner-prigozhin-criminal-case-explainer-intl/index.html

It sounds like Prigohzin could be a big headache for Putin.