A group of western Japan citizens sued the Kyoto governor on Wednesday for the return of taxpayer money used for him and other prefectural officials to attend a Shinto ceremony last year to mark Emperor Naruhito's enthronement, arguing their attendance violated the Constitution.

The plaintiffs claim Gov. Takatoshi Nishiwaki should return around ¥390,000 ($3,700) as his actions ran counter to the constitutional principle of separation of religion and state when he attended the Daijosai, a centuries-old overnight Shinto thanksgiving ceremony, held in November last year at the Imperial Palace in Tokyo.

In the suit filed with the Kyoto District Court, the 12 Kyoto residents also raise questions about the attendance by the governor and prefectural officials at a ceremony related to the Daijosai held in Nantan in the prefecture in September last year.