The Briefing Room's David Aaronovitch is joined by a team of experts to find out more about the Wagner group, the mysterious private organisation, that's acknowledged by the Russian government to have been supplying soldiers to fight its war in Ukraine. Wagner's leader, Yevgheny Prigozhin, was once known as Vladimir Putin's 'chef'. Soldiers fighting for him won the battle for Soledar - one of few military successes for Russia in Ukraine in recent months. Has his prowess on the battlefield re-invigorated Russia's army - or turned Prigozhin into a potential rival to Putin?Joining David Aaronovitch in The Briefing Room are: Samantha De Bendern, Associate Fellow at the Royal Institute of International Affairs, Chatham House Joana De Deus Pereira,Senior Research Fellow at the Royal United Services Institute Europe Marina Miron, Post-doctoral researcher at the Department of War Studies at King’s College London Andras Racz, Senior Research Fellow of the German Council on Foreign Relations in BerlinProduced by: Daniel Gordon, Ben Carter, Kirsteen Knight Edited by: Richard Vadon Sound engineer: James BeardPHOTO: Graffiti praising soldiers from the Wagner Group (Getty)