A Chinese teacher has been arrested on suspicion of poisoning his nursery school pupils after 23 children became ill.

Police in Jiaozuo said the teacher, identified by the surname Wang, is believed to have deliberately poisoned the children's food with sodium nitrate.

State-run news agency Xinhua said one child is seriously ill and seven others are being treated in hospital, although 15 have since been discharged.

The children started to vomit and faint after eating breakfast at the school, according to Beijing News.

One parent described arriving at the hospital after being notified by the school and discovering his child's stomach had been pumped.


Police say they are still looking for a motive for the attack, although local media said the teacher was trying to take revenge on a colleague.

Sodium nitrate is used as a food additive for curing meat but overexposure can be toxic and possibly fatal.

This would not be the first time schoolchildren in China have been the target of attacks by people bearing grudges or considered mentally ill.

In 2002, 42 people, mostly schoolchildren, died after eating food contaminated with rat poison in Nanjing.

The killer was later sentenced to death and executed.