Korean cries of protest echoed from speakers, not people, late on Feb. 24 in Seoul’s Gwanghwamun square.

“Public space must be open to the public! Stop using water cannons!”

More than 100 holographic protesters marched in front of an old palace gate in Seoul’s historic center plaza, broadcast by activists from Amnesty International Korea. Police looked on, taking notes and pictures but making no arrests, as the chants continued for 30 minutes.

“Authorities are banning more and more public protests, especially in central Seoul, citing reasons like traffic jams or public inconvenience,” said Kim Hee-jin, director of Amnesty International Korea, to Agence France-Presse. After the Seoul Metropolitan Police rejected Amnesty International Korea’s request to hold a demonstration, they tweaked their event and reported it as a “cultural activity.”

“We wanted to show that the situation has become so restrictive that only ghosts like these may freely march on the street,” the director said.

The organizers sent out a request for participants and messages, and recruited nearly 120 people to be filmed for the projection.

The demonstration coincided with the group’s release of their annual report, “State of the World’s Human Rights,” which cited multiple instances when authorities restricted citizens’ “rights to freedom of expression, association and peaceful assembly.” In 2015, police blocked roads, used water cannons and sprayed liquids with traces of chili pepper at protesters.

The holographic protest also fell on the day before South Korean President Park Geun-hye’s third inauguration anniversary.

The police had previously warned the group that their projection could violate the law, according to the Korea Times.

“If the event includes chanting indicative of a collective expression of opinion, it can be considered as a demonstration, and this means the rally would be illegal because the organizer did not report it in advance,” said Lee Sang-won, the Seoul police commissioner, on the day before the virtual rally. Violators could be punished with up to two years in prison, or a fine of 2 million won, which is about $1600.

The gathering was the first holographic protest in Korea, but not the first internationally. A virtual protest was staged in Spain in 2015 against a law setting high fines for demonstrators around public buildings.

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