The founder of a pro-Russian militia group in eastern Ukraine, described by authorities in Kyiv as a “criminal mastermind”, has died following a bombing in central Moscow, according to Russian state media.

Armen Sargsyan, the leader of a paramilitary unit wanted by Ukraine, died from his injuries following an explosion on Monday morning.

At least four other people were injured in the blast, which blew off one of the dead military leader’s legs and left his face so mangled that it was difficult at first to identify him,