Ten kindergarten pupils were injured when their school bus tipped onto its side in Harbin yesterday.
The accident happened when the children, all under the age of five, were on their way to kindergarten, Xinhua reported, citing local police.
Premier Wen Jiabao promised in his annual work report this year that the government would enhance school-bus safety.
Eight children who were sent to Harbin Red Cross Central Hospital have already been discharged. The two others, who suffered a broken collarbone and a head injury, were sent to Harbin Children's Hospital for treatment, a nurse said.
The accident is being investigated. It was not immediately clear whether the bus was overloaded.
Safety problems on school buses, especially in rural areas, have grabbed national headlines recently following a string of accidents that killed dozens of children.
Fifteen children died in December when a school bus plunged into a ditch in Fengxian, Jiangsu. It was carrying 87 children, 35 more than it should have been.
Two children were killed in another accident in December when a bus taking them on a field trip collided with a truck in Henan , and 37 were injured when a school bus was hit by a truck in Guangdong. And in November, 19 children and two adults were killed when a kindergarten van packed with 62 pupils collided with a truck in Gansu .
Such tragedies prompted the State Council to draft a new safety regulation for school buses for public consultation in December. It has yet to be implemented.
Under the draft guidelines, school buses would use lanes reserved for public transport. The draft also says that vehicles travelling behind a school bus should stop and wait whenever it pulls over to allow children to board or disembark.