Police in Shizuoka Prefecture, central Japan, have searched a nursery school in relation to the death of a pupil on Monday. The girl was pronounced dead after being left inside a school bus for about five hours.
Officers began searching the school in Makinohara City on Tuesday morning.
The three-year-old girl was found collapsed inside the bus shortly after 2 p.m. on Monday. She was rushed to a hospital but pronounced dead.
The police said the girl appears to have been left inside the bus after being picked up in the morning.
The 73-year-old headmaster of the school was driving the bus after the regular driver suddenly took the day off. In addition to him, six children including the girl and a non-regular staff member in her 70s were on the bus.
School staff reportedly told the police that usually the driver would make sure that all the children had gotten off after arriving at the school.
The police say they are conducting an investigation on suspicion of professional negligence resulting in death.