A screen displaying "ghost protesters" during a rally by Amnesty International in support of freedom of assembly and expression in South Korea. The human rights group pushed ahead with the "Ghost Protest" after police threatened a crackdown on the virtual rally consisting of holograms of about 120 people chanting slogans and waving banners on a giant screen set up in central Seoul on Sunday. The group said that the virtual march - the second in the world after a similar event in Spain last April - would protest against what it called the growing erosion of freedom of assembly and expression in the Asian country.