A dissident Russian journalist who was reported murdered in Kiev dramatically reappeared alive on Wednesday in the middle of a televised briefing about his own killing by the Ukrainian state security service.

Ukrainian authorities had said on Tuesday that Arkady Babchenko, a 41-year-old critic of President Vladimir Putin and of Russian policy in Ukraine and Syria, had been shot dead at his flat and that his wife had found him in a pool of blood.

His reported murder touched off a war of words between Ukraine and Russia, a flurry of condemnations from European capitals and Washington, and shivers through the journalistic communities in both countries.