Fears are growing that Iran is preparing to execute scores more protesters after authorities hanged a 23-year-old man from a crane, in a public killing carried out less than a month after he was arrested and following a secretive trial. Majidreza Rahnavard was sentenced to death by a court in the city of Mashhad, a centre of the protests, for allegedly killing two members of the paramilitary Basij force and wounding four others. The Basij, affiliated with the country’s feared Revolutionary Guards, has been at the forefront of the state crackdown. The pro-government Mizan news agency published a collage of...