
Nagako Tomioka, 58, chief priestess of Tomioka Hachimangū in Tokyo, was attacked by Shigenaga Tomioka, 56, as she got out of a car on Thursday evening. Media reports said he was her younger brother.
Also, a woman aged in her 30s who was with Shigenaga Tomioka attacked and stabbed the driver of the car with another katana, police said. The injuries to his shoulder and chest were not life-threatening.
After slashing the priestess, Shigenaga then stabbed the younger woman to death with a sword before killing himself, police said. The woman’s identity was not given.
Police declined to comment on the motive for the killings, but domestic media said the incident appeared to stem from a family feud.
Shigenaga sent a threatening letter to his sister in 2006, saying he would “send her to hell”, newspaper Sankei Shimbun said.
Japan has very restrictive gun laws and gun-related killings are rare.
Shinto is the traditional religion of Japan and many shrines dot the country. Tomioka Hachimangū, established in 1927, has a close link with sumo, and the emperor and empress visited in 2012.