BEIJING • A man wielding a knife killed nine children and injured 10 others outside a middle school in central China, the authorities said, in one of the worst attacks at a Chinese school in recent years.
The incident took place shortly after 6pm on Friday, officials said, as students were being dismissed at the Mizhi County No. 3 Middle School in Shaanxi province, about 800km south-west of Beijing.
The police said they had taken into custody a suspect, a man with the name Zhao, born in 1990. They said the man was a graduate of the middle school and he had told police he was seeking revenge because he had been bullied during his time there.
"He attacked students because he hated the students there," said a statement by the Mizhi County police posted on Weibo, a popular microblogging site.
Videos and images posted online by witnesses showed bodies spread along alleyways. Residents rushed for assistance, carrying the injured.
"Hurry up, hurry up, call for help!" a woman shouted in a video.
The police said the dead were seven girls and two boys.
Other videos showed police walking down a street holding the neck of a man whose face was bloody. Reports identified him as the suspect.
The attack revived fears in China about school safety, a perennial concern among parents. Knives are a weapon of choice in China, where guns and other weapons are strictly regulated.
"I thought campuses were safe without guns," one user wrote on Weibo.
Another user said it was necessary to take steps to stop more such attacks. "Revenge can't be forgiven but we need to find out how it began and prevent future cases."
In 2010, a spate of stabbings prompted the government to tighten security at schools, installing gates and cameras and training guards to fend off attackers.
Experts have pointed to a lack of high-quality mental health care in China and anxieties caused by social upheaval and persistent inequality in explaining the attacks.
Studies have described a rise in the prevalence of mental disorders, some of them linked to stress as the pace of life becomes faster and support systems wither.
While violent crime is rare in China, attacks have persisted.
In February, a knife-wielding man with a personal grudge killed a woman and injured 12 people in a busy Beijing mall - a rare act of violence in the heavily policed capital.
In the southern city of Shenzhen, a man armed with a kitchen knife killed two people and hurt nine others in a supermarket last July.
Attacks have also targeted schoolchildren in the past, forcing the authorities to increase security around schools.
In January last year, a man armed with a kitchen knife stabbed and wounded 11 children at a kindergarten in the southern Guangxi Zhuang autonomous region.
The previous February a knife-wielding assailant wounded 10 children in Haikou, in the southern island province of Hainan, before committing suicide. The man had entered the school, claiming that he was there to pick up his son.
The attacks have led to calls for more research into the root causes of such acts.
Assailants in school killings in China often receive severe punishments, including the death penalty.
NYTIMES, AGENCE FRANCE-PRESSE