A disability rights advocacy group staged a protest in a Seoul subway station that ended in the arrest of its leader a day after Seoul Metro announced a ban on protests by the group.

The police apprehended Park Kyoung-seok, the president of Solidarity Against Disability Discrimination(SADD), at around 8:50 a.m. during a protest on a platform at Hyehwa Station on Subway Line Four, which is operated by Seoul Metro

While being detained on charges of violating the Railway Safety Act and obstruction of business, Park complained of extreme chest pain and was taken to a nearby hospital.

Before the arrest, the SADD chief was holding a campaign against Seoul Metro’s decision to ban all subway protests by the group.

Seoul Metro said it came up with three-step countermeasures against SADD, which include blocking the group’s entry into subway stations, preventing them from boarding the trains by not opening or shutting the platform doors and taking legal action when applicable.