A 72-year-old former Self-Defense Forces officer who apparently killed himself and injured three others during a festival in Utsunomiya, Tochigi Prefecture, on Sunday, had been posting online messages about family troubles and warned of a desperate move.

Several social media accounts believed to have been written by Toshikatsu Kurihara hint about what might have led the pensioner to make such a move.

"I am desperate," read a post on a blog believed to have been written by Kurihara, whose mangled body was found Sunday in a park in the city.