A kindergarten student in China was left in the school bus, which was parked in the blistering heat for five hours. Three days after being rescued, the boy died of heat stroke.

The incident happened May 30 at Damao Golden Cradle Kindergarten in Wanning, Hainan province. When the school bus arrived at the institute at 8:30 a.m. local time (8:30 p.m. EDT, May 29), all the students got off except a four-year-old kid who had fallen asleep inside the vehicle. Meanwhile, the temperature in the city soared to 33 degrees Celsius (91.4 degrees Fahrenheit), Daily Mail reported.

Neither the bus driver nor the teachers of the school realized that the victim had not shown up for classes. At around 1:30 p.m. the child was found unconscious inside the vehicle. Although he was immediately rushed to the hospital, he could not be saved.

“My child was forgotten on the school bus - this is a serious dereliction of duty from the teacher and the driver,” the boy’s father told local news reporters.

Criminal investigations were launched against the driver and two female teachers of the kindergarten. All of them were detained by the police. Although the principal of the institute was initially placed under police custody, she was released as she was eight months pregnant.

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A school bus drives down a street in Manhattan's East Village on Jan. 15, 2013 in New York City. Mario Tama/Getty Images

Officials said the kindergarten was shut down and the students were sent to various other preschools in and around the area. A criminal charge against an official representing the preschool department of the Wanning Education Bureau was dismissed.

According to non-profit organization Kids and Cars, there was an average of 37 deaths among children every year from heat-related incidents after being trapped inside vehicles. In 55 percent of the cases, the children were unknowingly left behind.

The rate of hot car deaths in China is also pretty high. In April, a four-year-old girl, nicknamed Qi Qi, died after being left in a hot car for nine hours in Yiyang, Hunan province. The victim’s father was supposed to drop her off at the Wanyuan Kindergarten but she never turned up for her classes. Qi Qi’s father forgot to let her out of the car once they reached the destination and instead, became busy playing a game on his mobile phone. Later, without realizing that the toddler was still in the back seat of the car, he parked the vehicle at a parking lot and left with the child locked inside, while the temperature outside reached over 30 degrees Celsius (86 degrees Fahrenheit).