Education authorities in Japan are to discipline a teacher who forced two students to drink diluted hydrochloric acid, the latest incident to trigger concern over corporal punishment in the nation's schools.
The teacher, who has not been named but is from Gamagori, ordered the boys to drink the solution after they reported an incorrect result in a science experiment on January 18, the Nikkei Shimbun reported.
The incident only came to light when another student told his parents what had happened.
Officials of the local board of education in Aichi Prefecture, central Japan, said the teacher had informed them that the acid posed no danger to the children as it was diluted.
But the authorities were not convinced.
"As this incident posed a risk to the life and health of students, it was a grave failure of leadership and we can only apologise to the students and their families," the board said in a statement.
"We are currently deciding in disciplinary measures for the teacher involved."
The incident has focused new attention on the punishments meted out to children in Japan's schools.
Teachers are forbidden to use corporal punishment against pupils, but the suicide of a 17-year-old student on December 23 has demonstrated that it remains an integral part of school life here.
The boy was captain of the basketball team at Sakuranomiya Senior High School in Osaka and was repeatedly punished by his coach. The day before he was found hanging in his room, the boy was repeatedly slapped around the face for mistakes that he made in practice.
In a note to the coach that he never delivered, the boy wrote, "Even if I make the same mistakes as others, I get scolded harshly because I am the captain."
After the boy's suicide, 21 of the 50-strong basketball squad said they had been similarly punished by the coach.
Summoned by the local board of education to explain his actions, the coach said his methods were "a way to inspire the athletes."
In a press conference, an official of the board of education said, "We are truly sorry, but the fact remains that corporal punishment has never ceased to be practised at schools."