A 2-year-old girl died Saturday, possibly from heatstroke, after being left inside a car for most of the day when her father mistakenly thought he had dropped her off at a nursery school in Osaka Prefecture, according to police.

Seira Fuchigami's father, 33, told police that he left his home at around 8 a.m. with three of his children to drop them off. When he drove back to the school located in the city of Kishiwada after 5 p.m., staff told him that Seira had never arrived, leading him to search his vehicle where he found her limp and unconscious, according to police.

The girl was taken to hospital but was confirmed to have died. The father dropped off both his oldest and youngest daughters at a separate nursery school and returned home with Seira inside the car, the police said. He locked the car with its windows shut.

The mercury rose to 24.1 C in the nearby city of Sakai on Saturday, according to the weather agency.

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