Brutality of Russia's Wagner gives it lead in Ukraine war

Fierce battles in eastern Ukraine have thrown a new spotlight on Russia's Wagner Group, a private military company led by a rogue millionaire with longtime links to Russian President Vladimir Putin.

Wagner has spearheaded the push to jump-start Russia's stalemated offensive in eastern Ukraine's Donetsk province. The ferocious house-to house fighting has produced some of the bloodiest encounters since Russia sent troops into Ukraine, with Wagner personnel “marching on the bodies of their own soldiers” as Ukrainian authorities put it.

The U.S. this week expanded sanctions against Wagner for its role in Ukraine and mercenary activities in Africa.

Here is a look at the Wagner Group's history and its current role in the fighting.