The Metropolitan Police Department said Shin Futatsugi, the organizer of the demonstration, was taken into custody for violating a Tokyo Metropolitan Government Public Safety Ordinance, and the remaining 11, all men, were arrested for obstructing execution of public duties.
All suspects were part of a crowd of about 2,200 that marched around JR Shinjuku Station to protest Japan’s use of nuclear power generation.
Police said the arrests arose from one of the men punching a riot police officer in the face. Futatsugi’s arrest came about because he disobeyed regulations regarding protest marches, allowing demonstrators to use sidewalks instead of keeping only to the road as required, the MPD said.
Link to photographer Pierre Boutier’s pictures of the demonstration which he sent Majirox News: http://pierreboutier.photoshelter.com/gallery/12-antinuclear-activist-were-arrested-in-Shinjuku/G0000JFysOKxB_tQ/