Police have arrested three south China kindergarten workers after the death of a toddler who was left alone in sweltering temperatures on a school bus.

It is the third case in four months of a small child dying after being left alone in a school bus in China.

The police detained the driver and two teachers in south China's Guangdong Province for allegedly leaving the boy alone for three hours.

Tang Chongshu, who was 20 months old, was found unconscious at noon on Monday at the Fujing kindergarten in the Sanshui District of Foshan City. Teacher Zhu Fengxia discovered him when she went to the bus to get a quilt for an afternoon nap.

Tang was taken to Huali Hospital, but died at around 2:30 PM the same day after doctors tried to revive him. Doctors said the temperature was above 36 degrees Celsius at the time, and the boy died from the heat and lack of air.

Police said Zhu and fellow teacher Li Yongru picked up about 20 children in the morning, and arrived at the kindergarten around 9:00 AM. They allegedly failed in their duty of checking the roll and left the boy alone in the bus. The driver also allegedly failed to check the bus.

The township education authority has ordered the kindergarten to suspend classes. The kindergarten management said they would assume full responsibility for the boy's death and settle compensation with the parents, who were migrant workers from neighboring Guangxi region.

In May, a three-year-old boy died after being left alone in a school bus for six hours in east China's Anhui Province. Earlier this month, a boy of five died in similar circumstances in Jinan, capital of east China's Shandong Province.

(Xinhua News Agency August 23, 2007)