Kamata was born in 1940 and lived in Osaka prefecture. Between 1985 and 1994 he killed five people: four women and Sachiko Fujii, a nine-year-old primary school girl. He strangled them and dismembered the bodies, disposing of the parts in different places, and the remains of several were not found for years.
He was arrested in 1995 and tried in Osaka. He was sentenced to death on March 24, 1999, and the Osaka High Court upheld the sentence on March 26, 2002. The Supreme Court confirmed it in 2005.
He was executed by hanging on March 25, 2016, aged seventy-five, seventeen years after sentence. An interval that is ordinary in Japan, where the execution order is signed by the Minister of Justice at an unannounced time and prisoners are told on the morning.
The accessible record is Japanese press reporting of the trial and appeals. The killing of the child is what the case is remembered for in Osaka.