One web user, an apparent left-behind child who grew up with her grandmother, said she had been dragged by her hair and spat on during kindergarten and up to fourth grade in primary school.

"When I reported it to my teacher, he threw a question back in my face, 'why were you the only one being bullied?'" she recalled in her post, adding that the bullying did not stop until she was transferred to another school.

Another web user said she was sent to hospital for a week.

"The violent guys had good academic scores, and I was ugly and slow in school. The teacher just turned a blind eye," she said.

"My sense of inferiority has haunted me since then," she said, adding that the bullying she suffered at school has influenced her life.

The case has sparked discussion online on how to educate children to prevent them from being bullied.

An online survey on Weibo, which has drawn 100,000 participants, showed nearly two-thirds of parents would advise their children to take "a tooth for a tooth" response to bullying.

"I will tell my kid not to initiate a violent fight, but if he is bullied he has to fight back," one web user wrote.

Bullying and violence at schools and colleges have been widely reported in recent years. In late April, a video that showed a schoolgirl being repeatedly slapped by a group of older girls went viral.

In June 2014, another online video showed several teenagers in eastern Zhejiang Province burning a first-grade boy with cigarettes.

Last year, a junior-high student jumped from the fourth floor of a school building as he "just could not tolerate being bullied every day any longer."