The 44-year-old Tsarev, whose presidential bid has only the tiniest support, waited two hours at the studios before stepping out into the crowd where, despite some protection from his bodyguards, he was engulfed by a mob who threw eggs at him and then beat him.

He was hustled into a waiting ambulance but members of a far-right nationalist group Right Sector seized him and drove him first to the headquarters of the state security service and then to the prosecutor’s office.