Police are investigating how a Primary 3 girl landed in hospital after drinking from her water bottle to which a classmate had allegedly added liquid hand soap.

The victim had a fever and bouts of vomiting afterwards, Chinese evening daily Lianhe Wanbao reported yesterday.

The male classmate, nine, had reportedly wanted to help a friend from the same class who had had a falling out with the girl.

On Wednesday, the boy allegedly returned to their classroom during recess time to carry out the act.

The school is in Jurong.

Shortly after the girl drank from the bottle, she developed a fever and vomited twice. The school contacted her father to take her home.

The girl's father told Lianhe Wanbao that the family's maid was washing the water bottle when she noticed soap bubbles. There was also a strong smell of Dettol.

She told the girl's father, who returned to the school to question the teachers, before taking his daughter to hospital.

He said the hospital had told the police about the case.

While doctors said his daughter would not be in any danger in the long term, she was still vomiting and remained in hospital as of yesterday.

The Dettol liquid hand soap used was actually a prize won by the victim in a lucky draw held in school on the same day. Her father told Wanbao it had been left on a desk in the classroom.

On Thursday night, the boy visited the girl at the hospital, accompanied by his 27-year-old mother and a teacher, Wanbao reported.

The boy stood by the girl's bedside crying as he told her: "Sorry."

The boy's mother also apologised to the girl's family at the hospital.

She said her son did not have many friends in school, and that he poured the liquid soap into the girl's bottle on his friend's instruction, as he did not want to jeopardise their friendship.

The school is offering assistance to the girl's family, said Wanbao.

Ng Huiwen