Hong Kong CNN  — 

A kindergarten teacher who poisoned 25 children, killing one of them, after an argument with a rival staff member has been sentenced to death by a court in central China.

In its official ruling Monday, the Jiaozuo Intermediate People’s Court in Henan province described killer Wang Yun’s motives as “despicable” and “vicious.” “She should be punished severely in accordance with the law,” the ruling said.

The court heard that in the lead-up to the poisoning, Wang had quarreled with another teacher at the Jiaozuo kindergarten over how best to handle the students.

Then, on the morning of March 27, 2019, Wang added nitrite to porridge supplied by the school and intended for the other teacher’s students. Wang had previously bought the nitrite online.

According to the US Centers for Disease Control and Prevention, nitrite is toxic and a likely carcinogen used in fertilizers, food preservation and even munitions and explosives. At high levels, it can stop the human body from properly absorbing oxygen.

Wang had previously been caught trying to poison her husband, surnamed Feng, in February 2017 after an argument. On that occasion, Wang poured nitrite into a glass used by Feng, causing minor injuries.

At the time of the 2019 kindergarten poisoning, one parent told China’s state-run tabloid Global Times he had received a call from the kindergarten saying his child had vomited and fainted. When he arrived, his child was unconscious.

“The vomit was all over (their) pants. There were other children who were also throwing up, and they looked pale,” the father, surnamed Li, said.

Allegations of needle injuries

Wang’s sentence comes amid fresh allegations of the mistreatment of children at a kindergarten in northern China.

Eight parents claimed to have found unknown needle marks on their children’s heads and bodies after they returned from Zhaojun Dingqi Kindergarten in Hohhot, in the autonomous region of Inner Mongolia, state media Xinhua said.

According to Xinhua, when asked about the needle holes, the children told their parents that their teacher stabbed them with “toothpicks” and “red needles” for not behaving in class – and ordered them to not tell their families.

In a statement, the Xincheng district police said three women had been detained on suspicion of “torturing children under their guardianship,” although the case remains under investigation.

The Dingqi kindergarten said in a statement that while the school apologized for the concern and worry caused to parents, it had not yet found any evidence to substantiate the claims.

“At present, (we) have cooperated with the police to provide relevant surveillance footage and equipment, and cooperated with the investigation by the public security department,” the statement said.

In November 2017, a Beijing kindergarten teacher was sentenced to 18 months in prison for piercing four children in her class with needles. Police said the teacher, surnamed Liu, was using the needles to “tame” children, according to state-run tabloid Global Times.

CNN’s Beijing bureau contributed to this article.