Russian police have dropped drugs charges against journalist Ivan Golunov, a rare U-turn by the authorities in the face of anger from his supporters who alleged he was framed for his reporting and threatened to stage a mass protest in Moscow.

Police has said that a Russian investigative journalist who was detained this week for alleged drug offences had been taken to hospital, Russian news agencies reports.

A prominent Russian journalist and critic of President Vladimir Putin is shot dead in Ukraine where he had fled into exile following threats, police say.