SHANGHAI, Sept. 21 -- CHINA'S top education authority has ordered public kindergartens to allocate one teacher to sit on each school bus after some children were left on a bus and suffocated to death in hot weather, Xinhua news agency reported today.

The teacher should check the number of children before they get onto the bus and right after they get off, while the driver should thoroughly check the vehicle after students get off to make sure no one is left on it, said the State Ministry of Education in a statement issued yesterday.

The statement ordered local education departments to set tougher qualification standards for school bus drivers and vehicles.

Assembled vans or vehicles in bad shape shall not be used as school buses, it said. Private vehicles without school bus licenses are also banned, the statement said.

Officials should also ensure buses aren't overloaded.

In the past five months, three small children have died from heat after being left alone on school buses in Jinan City of Shandong Province, Foshan City of Guangdong Province and Guangdong's Dongguan City.

Teachers and workers involved have been detained by local police.

These accidents have raised public concerns over the administration and qualification of some public kindergartens and their employees, said the statement.

No unit or individual is allowed to open education facilities accepting children younger than six years without approval, said the statement.

Teachers and other employees should take safety training courses, it added.