A former principal of a kindergarten in Shizuoka Prefecture, central Japan, was referred to prosecutors on Monday for alleged professional negligence resulting in death after a 3-year-old girl died of heatstroke in a van used by the school three months ago.

Police say that Tatsuyoshi Masuda, 73, who headed Kawasaki kindergarten in Makinohara, was responsible for China (pronounced chee-na) Kawamoto's death on Sept. 5, after she was left behind on the van for about five hours. Three others were also referred to prosecutors over the case.

Photo taken on Sept. 14, 2022, in Makinohara, Shizuoka Prefecture, shows the vehicle in which 3-year-old China Kawamoto was left behind. (Kyodo)

The Shizuoka prefectural police had been investigating if there were any problems regarding the school's operation and its safety management system, based on documents recovered from their searches.

The van, which he drove that day, arrived at the kindergarten at around 8:50 a.m. School staff found the girl unconscious inside the van at around 2:10 p.m., with an empty water bottle, according to police.

Five other children and a staff member in her 70s had also boarded the vehicle, but the adults failed to notice that not everybody had disembarked.

Masuda apologized two days after the incident at a press conference, acknowledging that they "did not conduct safety management thoroughly."

A similar death by heatstroke occurred in July 2021 involving a 5-year-old boy in Nakama, Fukuoka Prefecture. He was left in a nursery school bus for about nine hours before being discovered.

The school's former head was sentenced to two years in prison and a staff member to 18 months, both suspended for three years, for negligence resulting in death.

These incidents prompted the government to compile emergency countermeasures in October that mandate safety devices like buzzers or sensors to be installed on school buses.

Related coverage:

FOCUS: Japan to compile stricter school bus safety rules after toddler dies

3-yr-old dies after left in bus for hours, heatstroke suspected