This file photo taken on March 23, 2010, shows people gathered grieving for children who were killed after a former doctor hacked eight children to death with a machete and injured five others at a primary school in Nanping, in southeast Chinas Fujian province. — AFP

BEIJING A jobless knife-wielding man attacked and injured 28 young children and three adults at a kindergarten in eastern China on Thursday in the third school stabbing frenzy in a month, state media said.

Five of the children were in critical condition after the attack in the city of Taixing, according to Xinhua news agency, citing officials and police.

The alleged assailant, a 47-year-old man identified as Xu Yuyuan, was detained following the incident in Jiangsu province, the report said.

The man burst into a classroom with a 20-centimetre knife and started attacking the children, most of whom were four years old, Xinhua said.

Two teachers and a security guard who tried to stop him were also hurt.

Various websites said there had been reports of up to four deaths in the morning attack, but an official with the Taixing city government told AFP it had so far received no such information.

“The gate-keeper, teachers, and students were attacked. The injured are receiving treatment in hospital. We dont have any reports of deaths yet,” said the official, who declined to be named.

Photos posted on Chinese websites showed dozens of people gathered outside the school, many of them apparently frantic parents.

The attack comes just a day after a teacher who had been on sick leave since 2006 for mental problems injured 15 students and a teacher in a knife attack at a school in southern China.

In Wednesdays attack in Guangdong province, Chen Kangbing, 33, burst into a primary school in the city of Leizhou and began stabbing students, Xinhua said.

He then jumped from a school building in an apparent suicide attempt before being arrested by police, reports said.

Chen, who worked at a different school in the area, was unable to answer questions during a psychological evaluation. All the injured were in stable condition, Xinhua said.

That attack occurred the same day that authorities in Fujian province in the southeast executed former doctor Zheng Minsheng for stabbing to death eight children on March 23.

Police said Zheng, 41, used a dagger to stab children in the neck, chest, stomach and back in a fit of rage and depression after splitting from his girlfriend. Five other children were seriously injured in the attack.

Zheng had admitted “intentionally killing” the children at a trial earlier this month, but had unsuccessfully appealed against the death penalty.

Such large-scale violence remains rare in China. However, crime rates have risen steadily since the country began opening up economically three decades ago.

Various recent studies also have cited a rise in mental disorders, often linked to psychological stress as society becomes more fast-paced and after the government scrapped the cradle-to-grave social supports of the past.

Extremely tight gun laws, however, prevent the death tolls in such attacks from reaching the levels seen occasionally in shooting attacks in some Western countries.